mutationn.

Brit.

/mjuːˈteɪʃn/, U.S.

/mjuˈteɪʃ(ə)n/

Forms: Middle English mutacyoun, Middle English mutasion, Middle English mwtacyoun, Middle English–1500s mutacion, Middle English–1500s mutacioun, 1500s mutacyon, 1500s– mutation; Scottish pre-1700 mutacion, pre-1700 mutacioun, pre-1700 mutacioune, pre-1700 mutatioun, pre-1700 mwtatione, pre-1700 1700s– mutation.

Origin: Of multiple origins. Partly a borrowing from French. Partly a borrowing from Latin. Etymons: French mutation; Latin mūtātiōn-, mūtātiō.

Etymology: < Anglo-Norman and Middle French, French mutation change (late 13th cent. in Old French as mutacion ), revolt (mid 15th cent.), change in physiology of a species (1766 in Buffon) and its etymon classical Latin mūtātiōn-, mūtātiō change, alteration, in post-classical Latin also in senses 3 (4th cent.), and 2a (9th cent. or earlier in musical treatises) < mūtāt- , past participial stem of mūtāre to change (see mutate v.) + -iō -ion suffix¹.In sense ‘revolution’ (see sense 1b) perhaps partly after Middle French meutacion riot, revolt (early 15th cent.) < meute uprising (see mute n.¹). In sense 2b translating ancient Greek μεταβολή modulation (see metabole n.). With mutation stop (see sense 2c) compare French jeux de mutation (1840). In sense 6a after German Mutation (W. Waagen Die Formenreihe des Ammonites Subradiatus (1869)). In sense 7a after German Mutation (H. de Vries Die Mutationstheorie (1901)).

a. The action or process of changing; alteration or change in form, qualities, etc.; an instance of this.

ΘΚΠ

the world > time > change > [noun]

wendingeOE

changing?c1225

stirringa1240

wrixlinga1240

changec1325

variancec1340

transmutationc1380

varyingc1380

whileness1382

translationc1384

alterationa1398

mutationa1398

removinga1425

revolutiona1425

shiftingc1440

changementc1450

muance1480

commutation1509

altry1527

transition1545

turning1548

novation1549

immutation?c1550

alterance1559

alienation1562

turn?1567

vicissitude1603

refraction1614

fermentationa1661

diabasis1672

parallax1677

motion1678

aliation1775

transience1946

a1398 J. Trevisa tr. Bartholomaeus Anglicus De Proprietatibus Rerum (BL Add.) f. 121 Þere is double mevinge of mutacioun and chaungeinge: ouþir þe meovinge is of chaunginge fro place to place oþir of chaunginge of disposicyoun in to anoþir disposicioun.

?a1425 (c1380) G. Chaucer tr. Boethius De Consol. Philos. i. pr. vi. 89 Weenestow that thise mutacions [L. uices] of fortunes fleten withouten governour.

c1450 tr. G. Deguileville Pilgrimage Lyfe Manhode (Cambr.) (1869) i. xli. 24 Al mutacioun that is doon in haste j hate.

a1475 (?a1430) J. Lydgate tr. G. Deguileville Pilgrimage Life Man (Vitell.) 3280 (MED) To hem he gaff pleynly power To maken..That merveyllous mutacion, Bred in-to flesshe, wyn in-to blood.

1517 R. Fox Let. 30 Apr. (1929) 92 The state and condicion of the toune and marches of Calis..and of theyr ruynes, decayes, mutacyons and alteracions fro the auncyent estatutz and ordinances [etc.].

1523 Ld. Berners tr. J. Froissart Cronycles I. clv. 187 It is come to the kynges knowledge, howe that his subgettes ar sore greued by reason of the mutacyon of y^e moneys.

1608 W. Shakespeare King Lear xv. 8 O world! But that thy strange mutations make vs hate thee, Life would not yeeld to age.

1655 G. S. in S. Hartlib Reformed Common-wealth Bees 21 I took the pain to observe and collect the Generation of several Insects, with their various mutations from kind to kind.

1710 M. Chudleigh Ess. Several Subj. 42 Upon the whole, if our Souls are immortal..they are not liable to the least Mutation.

1776 C. Burney Gen. Hist. Music I. 61 The Mutations..or changes incident to melody; which, in modern music, we should call..modulation.

1825 H. Smith Gaieties & Gravities I. 139 Since first thy form was in this box extended, We have above-ground, seen some strange mutations.

1876 A. R. Wallace Geogr. Distrib. Animals I. iii. 171 (sub-heading) A review of the chief forms of life in the several regions and sub-regions, with the indications they afford of geographical mutations.

1892 R. L. Stevenson & L. Osbourne Wrecker vi. 81 More than three years had intervened—almost without mutation in that stationary household.

1944 A. Nin All-seeing in Circle I. iv. 4 He was constantly in mutation between fierceness and yielding.

1982 V. Brome Ernest Jones xxiii. 213 Biography has undergone many mutations as a species.

†b. Change in government; revolution, civil upheaval; revolt, insurrection. Obsolete.

ΘΚΠ

society > authority > lack of subjection > rebelliousness > insurrection > [noun]

arising1340

rebeltyc1384

rebellion1409

rebela1425

insurrection1459

commotion1471

mutationa1513

revolting1539

mutine1560

head1597

sollevation1605

sublevation1612

liftinga1662

insurgence1863

society > authority > lack of subjection > rebelliousness > revolution > [noun]

uparisingc1325

mutationa1513

revolution1555

innovation1601

novation1603

conversion1614

smash1890

a1513 J. Irland Meroure of Wyssdome f. 345^v, in Dict. Older Sc. Tongue at Mutacio(u)n(e Mutacioun and changeing of princis and lawis is caus to waik the strenth and dignite of thame.

1530 tr. Caesar Commentaryes x. 12 He douted lest in his absence there shuld arise some chaunge or mutacyon in Fraunce.

1596 J. Dalrymple tr. J. Leslie Hist. Scotl. (1888) I. 164 Heireftir meruellous mutatiounis war sein in Britannie throuch the controuersies..betuene the Capitanis and the men of weir.

1649 To Sacred Maj. iv, in Famous Trag. King Charles I sig. A^v Strange revolution, O accurst mutation That appoints Coblers for to rule a Nation.

1660 J. Milton Readie Way Free Commonw. (ed. 2) 41 We had bin then by this time firmly rooted past fear of commotions or mutations.

1737 W. Whiston tr. Josephus Jewish War i. xvi, in tr. Josephus Genuine Wks. 721 He..exacted the tribute..as a penalty for the mutations they had made in the countrey.

†c. Changeableness, fickleness; inconstancy of character; an instance or the result of this. Obsolete.

ΘΚΠ

the world > time > change > changeableness > [noun]

unstablenessc1340

varyingc1380

uncertaintyc1384

brotelnessc1386

were1390

instabilityc1422

bricklenessa1425

changeability?a1425

changeableness1447

vertibility1447

mutability?a1475

variableness?a1475

inconstance1509

mutationa1542

fickleness1548

variety1548

unconstancy1563

mobility1567

unstability1572

vicissitude1576

variousness1607

inconstancy1613

slipperinessa1618

alterableness1633

versatilousness1640

bottomlessness1642

lability1651

brittlety1652

versatileness1654

fluctuancy1659

fugitivenessa1661

alterability1661

permutability1662

unfixedness1668

mutablenessa1677

flittingnessa1680

frailness1687

flittiness1692

versability1721

plasticity1727

variability1771

unestablishment1776

fluctuabilitya1786

changefulness1791

unsettledness1799

versatility1802

harlequinism1808

fluidity1824

fitfulness1825

sensitiveness1825

insubstantiality1848

contingency1858

rootlessness1859

shiftingness1866

ficklety1888

variancy1888

impredicability1906

proteanism1909

a1542 T. Wyatt Coll. Poems (1969) III. 109 In the be no alteration But that we men, like as our sellffes we say, Mesuryng thy Justice by our Mutation.

1548 Hall's Vnion: Edward IV f. ccxij Suche is the mutacion of the common people, like a rede with euery wind is agitable & flexible.

1569 E. Fenton tr. P. Boaistuau Certaine Secrete Wonders Nature f. 63^v They neuer at any time founde mutation in hym.

1712 E. Ward Misc. Writings (ed. 2) III. 215 Women are subject to mutation: Tho' some will say, the fickle Dame, That's always changing's still the same.

1823 M. W. Shelley Valperga III. iii. 54 She was herself so steady in her principles..that she was at a loss to understand the variable feelings and swift mutations of the poor, untaught Beatrice.

2. Music.

a. In medieval and early modern solmization: the change from one hexachord to another, achieved by changing the syllable applied to a given note.

ΘΚΠ

society > leisure > the arts > music > musical sound > pitch > system of sounds or intervals > [noun] > hexachord > change of hexachords

mutation1597

1597 T. Morley Plaine & Easie Introd. Musicke Annot. sig. ¶4 Mutation is the leauing of one name of a note and taking another in the same sound.

1609 J. Dowland tr. A. Ornithoparchus Micrologus 16 To a Musitian..Mutation is..the putting of one concord [L. vox consona] for another in the same Key.

1721 A. Malcolm Treat. Musick 540 Of Mutations. This signifies the Changes or Alterations that happen in the Order of the Sounds that compose the Melody.

1977 Early Music 5 474/1 Regular mutation, then, is a device for moving around within the gamut.

1980 Grove Dict. Music XVII. 460/1 For the occasional excursion by a semitone outside the hexachord range, a mutation was often not invoked.

†b. In ancient Greek music: a process similar to modulation in modern music (the sixth part of harmonics in the classification of Aristoxenus and his followers). Obsolete.

ΚΠ

1761 Philos. Trans. 1760 (Royal Soc.) 51 743 The author is speaking of the sixth division of harmonic, which was mutation.

1807 J. Robinson Archæol. Græca v. xxiii. 534 In music the Greeks distinguished..rhythmus, mutations, and melopœia.

c. In full mutation stop. An organ stop whose pipes sound one of the non-octave overtones of the fundamental note corresponding to the key struck. See also mutation rank n. at Compounds.

ΘΚΠ

society > leisure > the arts > music > musical instrument > keyboard instrument > organ > [noun] > stop > mutation stops

mutation stop1855

mutation rank1880

1855 E. J. Hopkins Organ 110 Mutation or Filling-up Stops do not give a sound corresponding with the key pressed down; but some sound g on the C key, others e.

1977 Gramophone Aug. 318/2 A modest-sized two-manual of only 20 stops,..is perfectly adequate, provided it has two main departments of more or less equal balance, and with good mutations, mixtures and reeds.

1980 Grove Dict. Music XII. 872/1 In modern organ usage, mutations are those single-rank stops..pitched at the 5th, 3rd, 7th, 9th, etc, of an upper octave... In classical French usage, mutation stops include any rank.

†d. A shift of hand position when playing the violin. Obsolete. rare.

ΚΠ

1890 Cent. Dict. Mutation,..the shifting of the hand from one position to another.

†3. Roman History. A place on a highway where post-horses could be changed. Obsolete.

ΘΚΠ

society > travel > transport > transport or conveyance in a vehicle > transport by relays of horses or vehicles > [noun] > a relay or change of horses > place where horses changed

postage1603

stage1603

mutation1610

relay1706

1610 P. Holland tr. W. Camden Brit. i. 65 Also Mutations; For so they called in that age, the places where strangers, as they journeied, did change their post-horses.

1677 R. Plot Nat. Hist. Oxford-shire 326 Pillars of stone, whereon they inscribed the distances from the regal Cities, Stations, and Mutations.

4. Law.

†a. mutation of libel n. amendment of the charges grounding a legal action. Cf. libel n. 3. Obsolete.

ΚΠ

1685 H. Consett Pract. Spiritual Courts (1700) iii. i. §2 82 We now come to the other part of Mynsinger his purpose (Scil.) the mutation or changing of Libels; mutare Libellum, to change the Libel, is to vary and alter the substance of it.

1856 Bouvier's Law Dict. U.S.A. (ed. 6) II. 195 Mutation of libel, practice. An amendment allowed to a libel, by which there is an alteration of the substance of the libel.

b. In French and Canadian law: transfer of the rights to property, etc. Frequently attributive, esp. in mutation duty, mutation fine.

ΚΠ

1825 Act 6 George IV c. 59 §5 [In Lower Canada] Every..droit de lods et ventes, and mutation fine of every description.

1856 Bouvier's Law Dict. U.S.A. (ed. 6) II. 195 Mutation, French law... Applied to designate the change which takes place in the property of a thing in its transmission from one person to another... It is nearly synonymous with transfer.

1914 Chancery Rep. I. 847 According to French law mutation duty was payable by the legatee on these chattels.

1939 M. Miner St. Denis i. 6 If these rights were sold, the seigneur received mutation fines, known as lods et ventes.

5. Linguistics.

a. Any (historical) phonological change. Cf. permutation n. 4. Now rare except in spec. senses below.Mutation is not now used in connection with Sanskrit phonology.

ΘΚΠ

the mind > language > linguistics > study of speech sound > speech sound > consonant > [noun] > addition or interchange of spec.

mutation1808

permutation1843

mimation1873

betacism1885

1808 C. Wilkins Gram. Sanskrĭta Lang. ii. 25 (heading) Mutations of final consonants.

1810 H. P. Forster Ess. Princ. Sanskrit Gram. I. ii. 15 The subject of the present Chapter is divided into the following heads: 1st, General Rules for the coalescing and Mutation of the final and initial Vowels of distinct Words... 5th, General Rules relative to the Mutation of the final and initial Consonants of distinct words.

1838 N. Amer. Rev. Apr. 504 The construct and suffix forms [of Hebrew], the plural forms, with all their mutations of vowels, we are left to guess out.

1897 N.E.D. at Dutch sb. That [sc. the form of German]..which has not undergone the High German consonant-mutation.

1994 J. Edwards Multilingualism (1995) ii. 53 Saussure intended his remarks to apply specifically to linguistic changes such as consonantal mutation, diphthongization and so on.

b. In the Celtic languages: morphophonemic alteration of an initial consonant. More fully initial (consonant) mutation. Cf. eclipsis n. 2, lenition n. 2, soft mutation n. at soft adj. Compounds 2a.

ΘΚΠ

the mind > language > linguistics > study of speech sound > speech sound > sound changes > [noun] > mutation

mutation1843

1843 Proc. Philol. Soc. (1844) 1 124 That remarkable system of initial mutations of consonants which distinguishes the Celtic languages from all others in Europe.

1904 Athenæum 5 Nov. 621/3 If Welsh loses its mutations as South Wales is doing slightly, we shall be sorry.

1972 R. R. K. Hartmann & F. C. Stork Dict. Lang. & Linguistics 147/2 Consonants may also be affected, as in initial mutation, e.g. Welsh tad ‘father’, but fy nhad ‘my father’.

1992 D. Crystal Encycl. Dict. Lang. & Langs. 260 Initial mutations are a particular problem for foreign learners, as they hide the underlying phonological identity of a word.

c. In the Germanic languages: a vowel change arising from assimilation to an adjacent sound; = umlaut n. More fully vowel mutation. Cf. back mutation n. at back adj. 1e.

ΘΚΠ

the mind > language > linguistics > study of speech sound > speech sound > sound changes > [noun] > umlaut

modification1845

umlaut1852

mutation1875

metaphony1894

umlauting1938

1875–6 H. Sweet in Trans. Philol. Soc. 558 The mutation of original ā, which is written æ in WS.

1887 W. W. Skeat Princ. Eng. Etymol. 1st Ser. 211 In many instances, the original vowel of the root has suffered both mutation and gradation.

1927 E. V. Gordon Introd. Old Norse 298 In E[ast] N[orse] i-, R-, w-, and u-mutation were obliterated by the operation of analogy [etc.].

1965 Language 41 25 The presence of reflexes of mutation allophones..demands that we consider the various umlauts to be the result of a single phonetic tendency which was active in the Proto-Germanic period.

1972 R. R. K. Hartmann & F. C. Stork Dict. Lang. & Linguistics 147/2 Changes can affect the whole sound system of a language from one stage in its historical development to the next, e.g. umlaut or vowel mutation.

6. Palaeontology.

a. A discrete form or variety of a species present at a particular stratigraphic level and differing very slightly from forms in adjacent levels, esp. forming part of an orthogenetic series. Now historical.

ΚΠ

1883 Science 29 June 601/1 Each species may present a certain number of modifications, related to each other in time or in space, and designated respectively under the name of mutations or varieties.

1905 in Q. Jrnl. Geol. Soc. 61 p. lxxiii A mutation, in the palaeontological and original sense, may be defined as a contemporaneous assemblage of individuals united by specific identity of structure inter se, and by common descent from a known pre-existing species, from which they differ in some minute but constant character or characters.

1911 Encycl. Brit. XX. 586 The mutations of Waagen may possibly, in fact, prove to be identical with the ‘definite variations’ or ‘rectigradations’ observed by Osborn in the teeth of mammals.

1920 A. M. Davies Introd. Palaeontol. xii. 359 When a species can be traced, with gradual changes, through a number of zones, each zonal form is called a mutation, and may be denoted by the symbol of its zone.

1960 H. H. Swinnerton Fossils (1962) xvi. 91 To such recognisable steps in the evolution of organisms W. Waagen gave the name mutation.

†b. Apparent directional change in successive fossil types; orthogenetic evolution. Obsolete. rare.

ΚΠ

1894 Amer. Jrnl. Sci. 148 372 Bateson's results..emphasize strongly the difference between variation and that steady advance along certain definite lines which Waagen called mutation.

7. Biology.

a. An abrupt transition producing an organism with heritable characteristics differing markedly from those of the parent type, supposed by H. de Vries to provide a mechanism for the origin of new species (cf. mutation theory n., saltation n.); a distinct form of an organism so produced. Also: the process so characterized. Now historical.There was initial confusion as to whether these transitions were different in kind to the slight variations identified in many living and fossil species, which had been assumed to be the basis of evolution by natural selection, but for which there was as yet no satisfactory genetic explanation. With the acceptance of Mendelian genetics, de Vries's term was interpreted in a modern genetic sense (see sense 7b).

ΘΚΠ

the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation > mutant > species

mutation1901

1901 Jrnl. Royal Microsc. Soc. 439 Quite distinct from these are those abrupt..variations..which sometimes occur, and of which de Vries records a remarkable instance in the genus Œnothera. For such variations de Vries proposes the term mutations.

1901 Science 29 Nov. 841/1 The origination by mutation of a strongly marked and distinct variety of tomato from seed of an old and well-known variety.

1902 H. de Vries in Science 9 May 726/2 It is of course a matter of pure chance whether a mutation is or is not better adapted to the environment than the parent species.

1907 Athenæum 31 Aug. 242/1 By a mutation it [sc. a species] does not change itself, but simply produces a new type. The mutation ‘is allied to its ancestor as a branch is to a tree’.

1965 A. H. Sturtevant Hist. Genetics x. 62 It is ironic that few of the original mutations observed by de Vries in Oenothera would now be called mutations.

b. A change of any magnitude in the genetic material of an organism, which may in certain cases be inherited by subsequent generations resulting in the appearance of a novel form; (occasionally) spec. a deleterious change of this kind; (also) an altered gene or phenotypic character which has resulted from such a change. Also: the process by which such changes occur.The genetic changes which constitute mutation may involve the alteration of individual base pairs in DNA or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes.

ΘΚΠ

the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation

sporting of nature1666

sporting1827

saltation1870

mutation1904

point mutation1921

mutation pressure1929

macromutation1940

micromutation1940

mutagenesis1950

the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation > mutational change

mutation1925

subvital1951

1904 Science 15 Jan. 113/2 This character [sc. the long-haired character in the Angora guinea-pig] is probably a mutation, and as such behaves in accordance with the above hypothesis.

1919 Jrnl. Exper. Zool. 28 381 In our opinion, the attempted distinctions between ‘saltations’, ‘mutations’, and ‘variations of slight degree’ have led rather to confusion of thought than to clearer thinking. To us these are all a single class, ‘mutations’, and the term carries no restrictions of degree, covering the most extreme as well as the slightest detectable inherited variation.

1925 Genetics 10 117 If one thinks of mutations as being simply inherited changes, it becomes necessary to distinguish changes that involve whole chromosomes..and what have been called ‘point-mutations’ or ‘gene-mutations’.

1955 Sci. News Let. 25 June 409 Many mutations are lethal. If man-made irradiation increases the mutation rate, the result is sure to be harmful.

1957 I. Asimov Naked Sun (1958) xi. 145 Even the best gene analysis of parents can't assure that all gene permutations and combinations will be favourable, to say nothing of the possibility of mutations.

1971 J. Z. Young Introd. Study Man xxviii. 392 The cause of mutation is some faulty copying during replication of the DNA.

1974 Sci. Amer. Sept. 82 (caption) One-gene mutation is responsible for the difference between the beta chain of a normal hemoglobin molecule..and that of..the variant form responsible for sickle-cell anemia.

1990 Mutagenesis 5 531/1 These frequencies suggest that error-prone repair of DNA damage was involved in the mutation process.

1995 Denver Post 22 Jan. a14/1 Biologists determined that what appeared to be a guilty mutation..was in fact a so-called polymorphism, a harmless variation in the chemical makeup of some people's DNA.

c. An organism which has arisen by genetic mutation; a mutant.For earlier uses relating to de Vries's mutation theory, see sense 7a.

ΘΚΠ

the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation > mutant

sport of nature1601

lusus naturaea1661

sportling1723

sport1834

bud-sport1900

mutant1901

break1921

mutation1941

1941 Astounding Sci.-Fiction May 16/2 During that period our present wise rule of inspecting each infant for the mark of sin and returning to the Converter any who are found to be mutations was not in force.

1985 J. Morris Last Lett. from Hav vi. 49 This is the Hav mongoose, Herpestes hav, a mutation of the Indian mongoose.

1990 Here's Health Dec. 6/4 He..initiated a campaign against genetic mutations of plants.

Compounds

mutation mink n. a mink of a mutant strain having a fur colour different from normal; the fur of such a mink, or a garment made from this.

ΘΚΠ

the world > animals > mammals > group Unguiculata or clawed mammal > family Mustelidae (weasel, marten, otter, or badger) > [noun] > genus Mustela (weasel) > mustela vison (mink)

mink1612

vison1780

Silverblu1941

mutation mink1942

Aleutian1946

sapphire1951

sapphire mink1960

the world > textiles and clothing > clothing > types or styles of clothing > [noun] > made from specific material > skin > types of

coney1855

sealskin1858

mutation mink1942

1942 H. Bock in Amer. Fur Breeder Oct. 14 (title) Mutation mink and their use in coats.

1958 Vogue Jan. 12 (advt.) Natural pale beige mutation mink.

1966 R. Serjeant Mink on my Shoulder xi. 152 To the fur trade..the mutation mink means a mink of an abnormal colour or fur pattern that can be repeated at will.

1991 Women's Wear Daily (Nexis) 2 Apr. 11 Some 350,000 Lunaraine pelts will be offered along with 200,000 mutation mink skins in a variety of colors.

mutation pressure n. Genetics the tendency for recurrent mutation (rather than selection) to alter the frequency of a particular allele within a population, or more generally to affect the genetic constitution of an organism.

ΘΚΠ

the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation

sporting of nature1666

sporting1827

saltation1870

mutation1904

point mutation1921

mutation pressure1929

macromutation1940

micromutation1940

mutagenesis1950

1929 Amer. Naturalist 63 276 It might be suggested that mutation pressure is the factor which reduces useless vestigial organs beyond the stage at which they can exert any conceivable detemerious effect.

1962 D. J. Merrell Evol. & Genetics xxiv. 237 Theoretically mutation pressure alone could bring about evolution.

1996 R. Dawkins Climbing Mount Improbable (1997) iii. 71 Mutation pressure does not systematically drive in the direction of improvement.

mutation rank n. Music a rank of pipes controlled by a mutation stop (see sense 2c).

ΘΚΠ

society > leisure > the arts > music > musical instrument > keyboard instrument > organ > [noun] > stop > mutation stops

mutation stop1855

mutation rank1880

1880 C. A. Edwards Organs ii. xxi. 153 The proper balancing of the foundation and mutation ranks.

mutation rate n. Genetics the rate at which mutations occur in a given gene or the genes of a population, usually expressed per generation.

ΘΚΠ

the world > life > biology > laboratory analysis > measure > [noun] > rate

R1841

productivity1881

fusion frequency1924

mutation rate1930

turnover rate1943

1930 R. A. Fisher Genetical Theory Nat. Selection vi. 122 If..the mutation rates..are high enough to maintain any considerable genetic diversity, it will only be the best adapted genotypes which can become the ancestors of future generations.

1971 M. Levitan & A. Montagu Textbk. Human Genetics xvii. 649 Mutation rates are usually stated in terms of the number of changed genes per locus per generation.

1990 Sci. Amer. Dec. 70/2 The great genetic difference of the Khoisans (or Bushmen) would have to be explained as the result of a locally accelerated mutation rate.

This entry has been updated (OED Third Edition, June 2003; most recently modified version published online March 2022).

单词	mutation
释义	mutationn. Brit. /mjuːˈteɪʃn/, U.S. /mjuˈteɪʃ(ə)n/ Forms: Middle English mutacyoun, Middle English mutasion, Middle English mwtacyoun, Middle English–1500s mutacion, Middle English–1500s mutacioun, 1500s mutacyon, 1500s– mutation; Scottish pre-1700 mutacion, pre-1700 mutacioun, pre-1700 mutacioune, pre-1700 mutatioun, pre-1700 mwtatione, pre-1700 1700s– mutation. Origin: Of multiple origins. Partly a borrowing from French. Partly a borrowing from Latin. Etymons: French mutation; Latin mūtātiōn-, mūtātiō. Etymology: < Anglo-Norman and Middle French, French mutation change (late 13th cent. in Old French as mutacion ), revolt (mid 15th cent.), change in physiology of a species (1766 in Buffon) and its etymon classical Latin mūtātiōn-, mūtātiō change, alteration, in post-classical Latin also in senses 3 (4th cent.), and 2a (9th cent. or earlier in musical treatises) < mūtāt- , past participial stem of mūtāre to change (see mutate v.) + -iō -ion suffix¹.In sense ‘revolution’ (see sense 1b) perhaps partly after Middle French meutacion riot, revolt (early 15th cent.) < meute uprising (see mute n.¹). In sense 2b translating ancient Greek μεταβολή modulation (see metabole n.). With mutation stop (see sense 2c) compare French jeux de mutation (1840). In sense 6a after German Mutation (W. Waagen Die Formenreihe des Ammonites Subradiatus (1869)). In sense 7a after German Mutation (H. de Vries Die Mutationstheorie (1901)). 1. a. The action or process of changing; alteration or change in form, qualities, etc.; an instance of this. ΘΚΠ the world > time > change > [noun] wendingeOE changing?c1225 stirringa1240 wrixlinga1240 changec1325 variancec1340 transmutationc1380 varyingc1380 whileness1382 translationc1384 alterationa1398 mutationa1398 removinga1425 revolutiona1425 shiftingc1440 changementc1450 muance1480 commutation1509 altry1527 transition1545 turning1548 novation1549 immutation?c1550 alterance1559 alienation1562 turn?1567 vicissitude1603 refraction1614 fermentationa1661 diabasis1672 parallax1677 motion1678 aliation1775 transience1946 a1398 J. Trevisa tr. Bartholomaeus Anglicus De Proprietatibus Rerum (BL Add.) f. 121 Þere is double mevinge of mutacioun and chaungeinge: ouþir þe meovinge is of chaunginge fro place to place oþir of chaunginge of disposicyoun in to anoþir disposicioun. ?a1425 (c1380) G. Chaucer tr. Boethius De Consol. Philos. i. pr. vi. 89 Weenestow that thise mutacions [L. uices] of fortunes fleten withouten governour. c1450 tr. G. Deguileville Pilgrimage Lyfe Manhode (Cambr.) (1869) i. xli. 24 Al mutacioun that is doon in haste j hate. a1475 (?a1430) J. Lydgate tr. G. Deguileville Pilgrimage Life Man (Vitell.) 3280 (MED) To hem he gaff pleynly power To maken..That merveyllous mutacion, Bred in-to flesshe, wyn in-to blood. 1517 R. Fox Let. 30 Apr. (1929) 92 The state and condicion of the toune and marches of Calis..and of theyr ruynes, decayes, mutacyons and alteracions fro the auncyent estatutz and ordinances [etc.]. 1523 Ld. Berners tr. J. Froissart Cronycles I. clv. 187 It is come to the kynges knowledge, howe that his subgettes ar sore greued by reason of the mutacyon of y^e moneys. 1608 W. Shakespeare King Lear xv. 8 O world! But that thy strange mutations make vs hate thee, Life would not yeeld to age. View more context for this quotation 1655 G. S. in S. Hartlib Reformed Common-wealth Bees 21 I took the pain to observe and collect the Generation of several Insects, with their various mutations from kind to kind. 1710 M. Chudleigh Ess. Several Subj. 42 Upon the whole, if our Souls are immortal..they are not liable to the least Mutation. 1776 C. Burney Gen. Hist. Music I. 61 The Mutations..or changes incident to melody; which, in modern music, we should call..modulation. 1825 H. Smith Gaieties & Gravities I. 139 Since first thy form was in this box extended, We have above-ground, seen some strange mutations. 1876 A. R. Wallace Geogr. Distrib. Animals I. iii. 171 (sub-heading) A review of the chief forms of life in the several regions and sub-regions, with the indications they afford of geographical mutations. 1892 R. L. Stevenson & L. Osbourne Wrecker vi. 81 More than three years had intervened—almost without mutation in that stationary household. 1944 A. Nin All-seeing in Circle I. iv. 4 He was constantly in mutation between fierceness and yielding. 1982 V. Brome Ernest Jones xxiii. 213 Biography has undergone many mutations as a species. †b. Change in government; revolution, civil upheaval; revolt, insurrection. Obsolete. ΘΚΠ society > authority > lack of subjection > rebelliousness > insurrection > [noun] arising1340 rebeltyc1384 rebellion1409 rebela1425 insurrection1459 commotion1471 mutationa1513 revolting1539 mutine1560 head1597 sollevation1605 sublevation1612 liftinga1662 insurgence1863 society > authority > lack of subjection > rebelliousness > revolution > [noun] uparisingc1325 mutationa1513 revolution1555 innovation1601 novation1603 conversion1614 smash1890 a1513 J. Irland Meroure of Wyssdome f. 345^v, in Dict. Older Sc. Tongue at Mutacio(u)n(e Mutacioun and changeing of princis and lawis is caus to waik the strenth and dignite of thame. 1530 tr. Caesar Commentaryes x. 12 He douted lest in his absence there shuld arise some chaunge or mutacyon in Fraunce. 1596 J. Dalrymple tr. J. Leslie Hist. Scotl. (1888) I. 164 Heireftir meruellous mutatiounis war sein in Britannie throuch the controuersies..betuene the Capitanis and the men of weir. 1649 To Sacred Maj. iv, in Famous Trag. King Charles I sig. A^v Strange revolution, O accurst mutation That appoints Coblers for to rule a Nation. 1660 J. Milton Readie Way Free Commonw. (ed. 2) 41 We had bin then by this time firmly rooted past fear of commotions or mutations. 1737 W. Whiston tr. Josephus Jewish War i. xvi, in tr. Josephus Genuine Wks. 721 He..exacted the tribute..as a penalty for the mutations they had made in the countrey. †c. Changeableness, fickleness; inconstancy of character; an instance or the result of this. Obsolete. ΘΚΠ the world > time > change > changeableness > [noun] unstablenessc1340 varyingc1380 uncertaintyc1384 brotelnessc1386 were1390 instabilityc1422 bricklenessa1425 changeability?a1425 changeableness1447 vertibility1447 mutability?a1475 variableness?a1475 inconstance1509 mutationa1542 fickleness1548 variety1548 unconstancy1563 mobility1567 unstability1572 vicissitude1576 variousness1607 inconstancy1613 slipperinessa1618 alterableness1633 versatilousness1640 bottomlessness1642 lability1651 brittlety1652 versatileness1654 fluctuancy1659 fugitivenessa1661 alterability1661 permutability1662 unfixedness1668 mutablenessa1677 flittingnessa1680 frailness1687 flittiness1692 versability1721 plasticity1727 variability1771 unestablishment1776 fluctuabilitya1786 changefulness1791 unsettledness1799 versatility1802 harlequinism1808 fluidity1824 fitfulness1825 sensitiveness1825 insubstantiality1848 contingency1858 rootlessness1859 shiftingness1866 ficklety1888 variancy1888 impredicability1906 proteanism1909 a1542 T. Wyatt Coll. Poems (1969) III. 109 In the be no alteration But that we men, like as our sellffes we say, Mesuryng thy Justice by our Mutation. 1548 Hall's Vnion: Edward IV f. ccxij Suche is the mutacion of the common people, like a rede with euery wind is agitable & flexible. 1569 E. Fenton tr. P. Boaistuau Certaine Secrete Wonders Nature f. 63^v They neuer at any time founde mutation in hym. 1712 E. Ward Misc. Writings (ed. 2) III. 215 Women are subject to mutation: Tho' some will say, the fickle Dame, That's always changing's still the same. 1823 M. W. Shelley Valperga III. iii. 54 She was herself so steady in her principles..that she was at a loss to understand the variable feelings and swift mutations of the poor, untaught Beatrice. 2. Music. a. In medieval and early modern solmization: the change from one hexachord to another, achieved by changing the syllable applied to a given note. ΘΚΠ society > leisure > the arts > music > musical sound > pitch > system of sounds or intervals > [noun] > hexachord > change of hexachords mutation1597 1597 T. Morley Plaine & Easie Introd. Musicke Annot. sig. ¶4 Mutation is the leauing of one name of a note and taking another in the same sound. 1609 J. Dowland tr. A. Ornithoparchus Micrologus 16 To a Musitian..Mutation is..the putting of one concord [L. vox consona] for another in the same Key. 1721 A. Malcolm Treat. Musick 540 Of Mutations. This signifies the Changes or Alterations that happen in the Order of the Sounds that compose the Melody. 1977 Early Music 5 474/1 Regular mutation, then, is a device for moving around within the gamut. 1980 Grove Dict. Music XVII. 460/1 For the occasional excursion by a semitone outside the hexachord range, a mutation was often not invoked. †b. In ancient Greek music: a process similar to modulation in modern music (the sixth part of harmonics in the classification of Aristoxenus and his followers). Obsolete. ΚΠ 1761 Philos. Trans. 1760 (Royal Soc.) 51 743 The author is speaking of the sixth division of harmonic, which was mutation. 1807 J. Robinson Archæol. Græca v. xxiii. 534 In music the Greeks distinguished..rhythmus, mutations, and melopœia. c. In full mutation stop. An organ stop whose pipes sound one of the non-octave overtones of the fundamental note corresponding to the key struck. See also mutation rank n. at Compounds. ΘΚΠ society > leisure > the arts > music > musical instrument > keyboard instrument > organ > [noun] > stop > mutation stops mutation stop1855 mutation rank1880 1855 E. J. Hopkins Organ 110 Mutation or Filling-up Stops do not give a sound corresponding with the key pressed down; but some sound g on the C key, others e. 1977 Gramophone Aug. 318/2 A modest-sized two-manual of only 20 stops,..is perfectly adequate, provided it has two main departments of more or less equal balance, and with good mutations, mixtures and reeds. 1980 Grove Dict. Music XII. 872/1 In modern organ usage, mutations are those single-rank stops..pitched at the 5th, 3rd, 7th, 9th, etc, of an upper octave... In classical French usage, mutation stops include any rank. †d. A shift of hand position when playing the violin. Obsolete. rare. ΚΠ 1890 Cent. Dict. Mutation,..the shifting of the hand from one position to another. †3. Roman History. A place on a highway where post-horses could be changed. Obsolete. ΘΚΠ society > travel > transport > transport or conveyance in a vehicle > transport by relays of horses or vehicles > [noun] > a relay or change of horses > place where horses changed postage1603 stage1603 mutation1610 relay1706 1610 P. Holland tr. W. Camden Brit. i. 65 Also Mutations; For so they called in that age, the places where strangers, as they journeied, did change their post-horses. 1677 R. Plot Nat. Hist. Oxford-shire 326 Pillars of stone, whereon they inscribed the distances from the regal Cities, Stations, and Mutations. 4. Law. †a. mutation of libel n. amendment of the charges grounding a legal action. Cf. libel n. 3. Obsolete. ΚΠ 1685 H. Consett Pract. Spiritual Courts (1700) iii. i. §2 82 We now come to the other part of Mynsinger his purpose (Scil.) the mutation or changing of Libels; mutare Libellum, to change the Libel, is to vary and alter the substance of it. 1856 Bouvier's Law Dict. U.S.A. (ed. 6) II. 195 Mutation of libel, practice. An amendment allowed to a libel, by which there is an alteration of the substance of the libel. b. In French and Canadian law: transfer of the rights to property, etc. Frequently attributive, esp. in mutation duty, mutation fine. ΚΠ 1825 Act 6 George IV c. 59 §5 [In Lower Canada] Every..droit de lods et ventes, and mutation fine of every description. 1856 Bouvier's Law Dict. U.S.A. (ed. 6) II. 195 Mutation, French law... Applied to designate the change which takes place in the property of a thing in its transmission from one person to another... It is nearly synonymous with transfer. 1914 Chancery Rep. I. 847 According to French law mutation duty was payable by the legatee on these chattels. 1939 M. Miner St. Denis i. 6 If these rights were sold, the seigneur received mutation fines, known as lods et ventes. 5. Linguistics. a. Any (historical) phonological change. Cf. permutation n. 4. Now rare except in spec. senses below.Mutation is not now used in connection with Sanskrit phonology. ΘΚΠ the mind > language > linguistics > study of speech sound > speech sound > consonant > [noun] > addition or interchange of spec. mutation1808 permutation1843 mimation1873 betacism1885 1808 C. Wilkins Gram. Sanskrĭta Lang. ii. 25 (heading) Mutations of final consonants. 1810 H. P. Forster Ess. Princ. Sanskrit Gram. I. ii. 15 The subject of the present Chapter is divided into the following heads: 1st, General Rules for the coalescing and Mutation of the final and initial Vowels of distinct Words... 5th, General Rules relative to the Mutation of the final and initial Consonants of distinct words. 1838 N. Amer. Rev. Apr. 504 The construct and suffix forms [of Hebrew], the plural forms, with all their mutations of vowels, we are left to guess out. 1897 N.E.D. at Dutch sb. That [sc. the form of German]..which has not undergone the High German consonant-mutation. 1994 J. Edwards Multilingualism (1995) ii. 53 Saussure intended his remarks to apply specifically to linguistic changes such as consonantal mutation, diphthongization and so on. b. In the Celtic languages: morphophonemic alteration of an initial consonant. More fully initial (consonant) mutation. Cf. eclipsis n. 2, lenition n. 2, soft mutation n. at soft adj. Compounds 2a. ΘΚΠ the mind > language > linguistics > study of speech sound > speech sound > sound changes > [noun] > mutation mutation1843 1843 Proc. Philol. Soc. (1844) 1 124 That remarkable system of initial mutations of consonants which distinguishes the Celtic languages from all others in Europe. 1904 Athenæum 5 Nov. 621/3 If Welsh loses its mutations as South Wales is doing slightly, we shall be sorry. 1972 R. R. K. Hartmann & F. C. Stork Dict. Lang. & Linguistics 147/2 Consonants may also be affected, as in initial mutation, e.g. Welsh tad ‘father’, but fy nhad ‘my father’. 1992 D. Crystal Encycl. Dict. Lang. & Langs. 260 Initial mutations are a particular problem for foreign learners, as they hide the underlying phonological identity of a word. c. In the Germanic languages: a vowel change arising from assimilation to an adjacent sound; = umlaut n. More fully vowel mutation. Cf. back mutation n. at back adj. 1e. ΘΚΠ the mind > language > linguistics > study of speech sound > speech sound > sound changes > [noun] > umlaut modification1845 umlaut1852 mutation1875 metaphony1894 umlauting1938 1875–6 H. Sweet in Trans. Philol. Soc. 558 The mutation of original ā, which is written æ in WS. 1887 W. W. Skeat Princ. Eng. Etymol. 1st Ser. 211 In many instances, the original vowel of the root has suffered both mutation and gradation. 1927 E. V. Gordon Introd. Old Norse 298 In E[ast] N[orse] i-, R-, w-, and u-mutation were obliterated by the operation of analogy [etc.]. 1965 Language 41 25 The presence of reflexes of mutation allophones..demands that we consider the various umlauts to be the result of a single phonetic tendency which was active in the Proto-Germanic period. 1972 R. R. K. Hartmann & F. C. Stork Dict. Lang. & Linguistics 147/2 Changes can affect the whole sound system of a language from one stage in its historical development to the next, e.g. umlaut or vowel mutation. 6. Palaeontology. a. A discrete form or variety of a species present at a particular stratigraphic level and differing very slightly from forms in adjacent levels, esp. forming part of an orthogenetic series. Now historical. ΚΠ 1883 Science 29 June 601/1 Each species may present a certain number of modifications, related to each other in time or in space, and designated respectively under the name of mutations or varieties. 1905 in Q. Jrnl. Geol. Soc. 61 p. lxxiii A mutation, in the palaeontological and original sense, may be defined as a contemporaneous assemblage of individuals united by specific identity of structure inter se, and by common descent from a known pre-existing species, from which they differ in some minute but constant character or characters. 1911 Encycl. Brit. XX. 586 The mutations of Waagen may possibly, in fact, prove to be identical with the ‘definite variations’ or ‘rectigradations’ observed by Osborn in the teeth of mammals. 1920 A. M. Davies Introd. Palaeontol. xii. 359 When a species can be traced, with gradual changes, through a number of zones, each zonal form is called a mutation, and may be denoted by the symbol of its zone. 1960 H. H. Swinnerton Fossils (1962) xvi. 91 To such recognisable steps in the evolution of organisms W. Waagen gave the name mutation. †b. Apparent directional change in successive fossil types; orthogenetic evolution. Obsolete. rare. ΚΠ 1894 Amer. Jrnl. Sci. 148 372 Bateson's results..emphasize strongly the difference between variation and that steady advance along certain definite lines which Waagen called mutation. 7. Biology. a. An abrupt transition producing an organism with heritable characteristics differing markedly from those of the parent type, supposed by H. de Vries to provide a mechanism for the origin of new species (cf. mutation theory n., saltation n.); a distinct form of an organism so produced. Also: the process so characterized. Now historical.There was initial confusion as to whether these transitions were different in kind to the slight variations identified in many living and fossil species, which had been assumed to be the basis of evolution by natural selection, but for which there was as yet no satisfactory genetic explanation. With the acceptance of Mendelian genetics, de Vries's term was interpreted in a modern genetic sense (see sense 7b). ΘΚΠ the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation > mutant > species mutation1901 1901 Jrnl. Royal Microsc. Soc. 439 Quite distinct from these are those abrupt..variations..which sometimes occur, and of which de Vries records a remarkable instance in the genus Œnothera. For such variations de Vries proposes the term mutations. 1901 Science 29 Nov. 841/1 The origination by mutation of a strongly marked and distinct variety of tomato from seed of an old and well-known variety. 1902 H. de Vries in Science 9 May 726/2 It is of course a matter of pure chance whether a mutation is or is not better adapted to the environment than the parent species. 1907 Athenæum 31 Aug. 242/1 By a mutation it [sc. a species] does not change itself, but simply produces a new type. The mutation ‘is allied to its ancestor as a branch is to a tree’. 1965 A. H. Sturtevant Hist. Genetics x. 62 It is ironic that few of the original mutations observed by de Vries in Oenothera would now be called mutations. b. A change of any magnitude in the genetic material of an organism, which may in certain cases be inherited by subsequent generations resulting in the appearance of a novel form; (occasionally) spec. a deleterious change of this kind; (also) an altered gene or phenotypic character which has resulted from such a change. Also: the process by which such changes occur.The genetic changes which constitute mutation may involve the alteration of individual base pairs in DNA or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes. ΘΚΠ the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation sporting of nature1666 sporting1827 saltation1870 mutation1904 point mutation1921 mutation pressure1929 macromutation1940 micromutation1940 mutagenesis1950 the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation > mutational change mutation1925 subvital1951 1904 Science 15 Jan. 113/2 This character [sc. the long-haired character in the Angora guinea-pig] is probably a mutation, and as such behaves in accordance with the above hypothesis. 1919 Jrnl. Exper. Zool. 28 381 In our opinion, the attempted distinctions between ‘saltations’, ‘mutations’, and ‘variations of slight degree’ have led rather to confusion of thought than to clearer thinking. To us these are all a single class, ‘mutations’, and the term carries no restrictions of degree, covering the most extreme as well as the slightest detectable inherited variation. 1925 Genetics 10 117 If one thinks of mutations as being simply inherited changes, it becomes necessary to distinguish changes that involve whole chromosomes..and what have been called ‘point-mutations’ or ‘gene-mutations’. 1955 Sci. News Let. 25 June 409 Many mutations are lethal. If man-made irradiation increases the mutation rate, the result is sure to be harmful. 1957 I. Asimov Naked Sun (1958) xi. 145 Even the best gene analysis of parents can't assure that all gene permutations and combinations will be favourable, to say nothing of the possibility of mutations. 1971 J. Z. Young Introd. Study Man xxviii. 392 The cause of mutation is some faulty copying during replication of the DNA. 1974 Sci. Amer. Sept. 82 (caption) One-gene mutation is responsible for the difference between the beta chain of a normal hemoglobin molecule..and that of..the variant form responsible for sickle-cell anemia. 1990 Mutagenesis 5 531/1 These frequencies suggest that error-prone repair of DNA damage was involved in the mutation process. 1995 Denver Post 22 Jan. a14/1 Biologists determined that what appeared to be a guilty mutation..was in fact a so-called polymorphism, a harmless variation in the chemical makeup of some people's DNA. c. An organism which has arisen by genetic mutation; a mutant.For earlier uses relating to de Vries's mutation theory, see sense 7a. ΘΚΠ the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation > mutant sport of nature1601 lusus naturaea1661 sportling1723 sport1834 bud-sport1900 mutant1901 break1921 mutation1941 1941 Astounding Sci.-Fiction May 16/2 During that period our present wise rule of inspecting each infant for the mark of sin and returning to the Converter any who are found to be mutations was not in force. 1985 J. Morris Last Lett. from Hav vi. 49 This is the Hav mongoose, Herpestes hav, a mutation of the Indian mongoose. 1990 Here's Health Dec. 6/4 He..initiated a campaign against genetic mutations of plants. Compounds mutation mink n. a mink of a mutant strain having a fur colour different from normal; the fur of such a mink, or a garment made from this. ΘΚΠ the world > animals > mammals > group Unguiculata or clawed mammal > family Mustelidae (weasel, marten, otter, or badger) > [noun] > genus Mustela (weasel) > mustela vison (mink) mink1612 vison1780 Silverblu1941 mutation mink1942 Aleutian1946 sapphire1951 sapphire mink1960 the world > textiles and clothing > clothing > types or styles of clothing > [noun] > made from specific material > skin > types of coney1855 sealskin1858 mutation mink1942 1942 H. Bock in Amer. Fur Breeder Oct. 14 (title) Mutation mink and their use in coats. 1958 Vogue Jan. 12 (advt.) Natural pale beige mutation mink. 1966 R. Serjeant Mink on my Shoulder xi. 152 To the fur trade..the mutation mink means a mink of an abnormal colour or fur pattern that can be repeated at will. 1991 Women's Wear Daily (Nexis) 2 Apr. 11 Some 350,000 Lunaraine pelts will be offered along with 200,000 mutation mink skins in a variety of colors. mutation pressure n. Genetics the tendency for recurrent mutation (rather than selection) to alter the frequency of a particular allele within a population, or more generally to affect the genetic constitution of an organism. ΘΚΠ the world > life > biology > biological processes > genetic activity > [noun] > changes or actions of genes or chromosomes > mutation sporting of nature1666 sporting1827 saltation1870 mutation1904 point mutation1921 mutation pressure1929 macromutation1940 micromutation1940 mutagenesis1950 1929 Amer. Naturalist 63 276 It might be suggested that mutation pressure is the factor which reduces useless vestigial organs beyond the stage at which they can exert any conceivable detemerious effect. 1962 D. J. Merrell Evol. & Genetics xxiv. 237 Theoretically mutation pressure alone could bring about evolution. 1996 R. Dawkins Climbing Mount Improbable (1997) iii. 71 Mutation pressure does not systematically drive in the direction of improvement. mutation rank n. Music a rank of pipes controlled by a mutation stop (see sense 2c). ΘΚΠ society > leisure > the arts > music > musical instrument > keyboard instrument > organ > [noun] > stop > mutation stops mutation stop1855 mutation rank1880 1880 C. A. Edwards Organs ii. xxi. 153 The proper balancing of the foundation and mutation ranks. mutation rate n. Genetics the rate at which mutations occur in a given gene or the genes of a population, usually expressed per generation. ΘΚΠ the world > life > biology > laboratory analysis > measure > [noun] > rate R1841 productivity1881 fusion frequency1924 mutation rate1930 turnover rate1943 1930 R. A. Fisher Genetical Theory Nat. Selection vi. 122 If..the mutation rates..are high enough to maintain any considerable genetic diversity, it will only be the best adapted genotypes which can become the ancestors of future generations. 1971 M. Levitan & A. Montagu Textbk. Human Genetics xvii. 649 Mutation rates are usually stated in terms of the number of changed genes per locus per generation. 1990 Sci. Amer. Dec. 70/2 The great genetic difference of the Khoisans (or Bushmen) would have to be explained as the result of a locally accelerated mutation rate. This entry has been updated (OED Third Edition, June 2003; most recently modified version published online March 2022). < n.a1398
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