| 释义 |
ortho-
before a vowel sometimes orth-, combining form of Gr. ὀρθός ‘straight, right’, an element of various words, chiefly scientific or technical, sometimes in the physical sense ‘straight’, sometimes in the ethical sense ‘right, correct, proper’.
1. In technical words generally (for the more important of which see their alphabetical places): ˈortho-axis Cryst. = orthodiagonal; orthoˈbasic a. Cryst. [basic], applied to those systems of crystallization in which the axes are at right angles; orthoˈcarpous a. Bot. [Gr. καρπός fruit], having straight fruit; orthoˈchronograph (see quot.); orthocœlic |-ˈsiːlɪk|, orthoˈcœlous adjs. Zool. [Gr. κοιλία belly], having a straight intestine (as an infusorian), or the intestines arranged in straight or parallel folds (as a bird: opp. to cyclocœlic); ˈorthocone, the conical shell of certain fossil nautiloid cephalopods or a fossil characterized by a shell of this shape; hence orthoˈconic a., of or pertaining to a fossil or a shell of this type; ˈortho-cousin, one of cousins whose related parents are of the same sex (cf. cross-cousin s.v. cross- B); ˈorthocycle |-saɪk(ə)l| Geom. [Gr. κύκλος circle], the circle that is the locus of intersections of tangents to a conic at right angles to each other; the director circle; orthodiˈagonal Cryst., (a) n., that lateral axis in the monoclinic system which is at right angles to the vertical axis; (b) adj., belonging to or in the line of this axis (opp. to clinodiagonal); orthoˈdigita (see quot. 1939); hence orthoˈdigital a.; ˈorthodome Cryst. [dome n. 5 b], a dome parallel to the orthodiagonal in the monoclinic system; hence ˌorthodoˈmatic a., pertaining to an orthodome; orthoˈferrite, any of the compounds with the formula AFeO3, where A is a trivalent metal ion (usu. a rare earth), which have an orthorhombic crystal structure and exhibit weak ferromagnetism at room temperature; ˈorthoform Pharm. [after chloroform n.], methyl m-amino-p-hydroxybenzoate, C8H9NO3, a crystalline compound with anæsthetic properties which has been used as a dusting powder for wounds and ulcers and in dentistry; orˈthogamy Bot. [Gr. γάµος marriage] (see quot.); ˈorthogeoˈsyncline Geol. [ad. G. orthogeosynklinale (H. Stille 1935, in Sitzungsber. d. preuss. Akad. d. Wissensch. (Phys.-mat. Kl.) 182)], a linear geosyncline between a continental and an oceanic kratogen (craton), typically comprising a miogeosyncline and an adjacent eugeosyncline; hence ˌorthogeosynˈclinal a.; ˈorthoglossy nonce-wd. [Gr. γλῶσσα tongue, after orthography], correct pronunciation; ˈorthogneiss Petrogr. [a. G. orthogneiss (H. Rosenbusch Elem. d. Gesteinlehre (1898) 467)], gneiss derived from igneous rocks; orthokiˈnesis Zool. [kinesis 2], a kinesis in which linear movement is shown; hence orthokiˈnetic a.; ˌorthoperˈcussion Med., very light diagnostic percussion of the chest by means of one finger striking the knuckles of another bent at right angles and with its tip resting in an intercostal space; orthophony |ɔːˈθɒfənɪ| [Gr. ϕωνή voice, sound], the art of correct speaking or enunciation; hence orthoˈphonic a., pertaining to orthophony; reproducing sounds correctly; orthoˈphoria Ophthalm. [Gr. ϕορός bearing], the state of perfect oculomotor balance, in which the visual axes tend towards being parallel in the absence of a fusion stimulus; hence orthoˈphoric a.; ˈorthoˌphoto, orthoˈphotograph, an image produced optically or electronically from aerial photographs by eliminating distortions of angles and scales so as to give a result corresponding to a planimetric map; orthoˈphotomap, a map made up from an assembly of orthophotographs on which relief has been indicated by contours or shading; ˈorthophyre Petrogr. [a. F. orthophyre (H. Coquand 1856, in Mém. de la Soc. d'Émulation du Dép. du Doubs I. 64)], porphyry in which the phenocrysts are chiefly of orthoclase; orthoˈphyric a. Petrogr. [ad. G. orthophyrisch (H. Rosenbusch Mikrosk. Physiogr. (ed. 2, 1887) II. 594)], (of the groundmass of porphyritic rocks) containing short, stout feldspar crystals of rectangular or quadratic cross-section; orthoˈpinacoid Cryst. [pinacoid], one of the principal planes in the monoclinic system, parallel to the vertical axis and the orthodiagonal; hence orthopinaˈcoidal a.; ˈorthoploid a. Cytology [a. G. orthoploid (H. Winkler 1916, in Zeitschr. Bot. VIII. 422)], having a complete or balanced set of chromosomes: with most authors = euploid a.; ˈorthoprism Cryst., a prism in a monoclinic crystal, the faces of which are parallel to the vertical axis; orthoˈpyramid Cryst., in the monoclinic system a pyramid for which the ratio of the intercept made by it upon the orthodiagonal to that made upon the clinodiagonal is greater than the corresponding ratio for the primary pyramid; orthopyˈroxene Min. [ad. G. orthopyroxen (E. Düll, at the suggestion of F. Rinne, in Zeitschr. f. Krystallogr. und Mineral. (1902) XXXVI. 654)], any orthorhombic pyroxene; orˈtho(r)rhaphous a. Ent. [f. mod.L. Orthorhapha (later Orthorrhapha) (F. Brauer Monographie der Oestriden (1863) 33), f. Gr. ῥαϕή seam], belonging or pertaining to the suborder Orthorrhapha, a group of dipterous insects in which the adult emerges from the puparium through a straight or T-shaped split; cf. cyclorrhaphous adj. (cyclo-); ˈorthostyle Arch. [Gr. στῦλος column], a straight row of columns; orthotecˈtonic a. Geol. [ad. G. orthotektonik n. (H. Stille Einführung in den Bau Amerikas (1940) i. 9)] formed by, or of the nature of, a deformation which produces complicated and crowded systems of fold belts such as the Alps and is characterized by much magmatism and lateral thrusting (believed to be characteristic of orthogeosynclines); cf. paratectonic adj. (b) s.v. para-1 1; orthoˈtopic a. Med. and Biol. [Gr. τοπικ-ός of place], involving transplantation of a structure to the same site in the recipient as it occupied in the donor; also said of the transplanted structure; hence orthoˈtopically adv.; orˈthotypous a. Min. [Gr. τύπος type], ‘having a perpendicular cleavage’ (Webster, 1864); ˈorthovoltage Med., a voltage (in an X-ray tube) of the size used in conventional deep therapy (200–400 kilovolts); usu. attrib.; ˈorthowater = polywater.
1857Mayne Expos. Lex., Orthobasicus, applied by Naumann to systems of crystallization that are coördinate, orthagonal or rectangular, viz., the tessular, prismatic, pyramidal and rhombohedrical: *orthobasic.
1881West in Jrnl. Bot. X. 115 This species belongs to the *orthocarpous leiophyllous Hypnaceae.
1844Mech. Mag. XLI. 337 At the late meeting of the British Association, Dr. Robinson exhibited and explained the *Orthochronograph, an ingenious instrument recently introduced..[for] the ascertaining of correct time.
1882W. A. Forbes in Rep. Challenger Exp. IV. 10 The arrangement of the intestinal folds is ‘*orthocœlic’, the intestine being disposed in light folds lying close to and parallel with each other.
1857Mayne Expos. Lex., *Orthocelous. 1892Syd. Soc. Lex., Ortho⁓cœlous, having a straight or longitudinally ranged intestine.
1900A. Hyatt in C. R. Eastman tr. von Zittel's Textbk. Paleont. I. 573 An *orthocone is the young of the straight as well as many of the coiled forms [of fossil cephalopod]. 1935Twenhofel & Shrock Invertbr. Paleontol. ix. 368 Early cephalopod shells were dominantly straight or but slightly coiled... Among the Nautiloidea this type of shell is known as an orthocone. 1969Bennison & Wright Geol. Hist. Brit. Isles iv. 88 In the Durness sequence..the commonest fossils are gastropods..together with orthocone cephalopods. 1970R. M. Black Elements Palaeont. viii. 78 Orthoceras and similar orthocones range in length from about 3 cm to possibly 460 cm.
1926A. F. Foerste in Jrnl. Sci. Lab. Denison Univ. XXI. v. 304 (heading) *Orthoconic genera. Ibid. 310 The specimen is figured as having its ventral side ribbed and fluted vertically in a manner very similar to that of Kionoceras, a form of ornamentation unknown in any other orthoconic triangular cephalopod. 1935Twenhofel & Shrock Invertbr. Paleontol. ix. 367 (caption) Idealized diagram of an orthoconic cephalopod. 1974Nature 8 Feb. 396/1 Glaciomarine beds..in South West Africa have yielded..an orthoconic nautiloid.
1918J. G. Frazer Folk-Lore in Old Testament II. ii. vi. 98 It has become customary to call the marriageable cousins cross-cousins, because..the related parents are of opposite or cross sexes. There has hitherto been no special name for the unmarriageable cousins, the children of two brothers or of two sisters, but for convenience I propose to call them *ortho-cousins to distinguish them from cross-cousins. In the case of ortho-cousins the related parents are of the same sex. 1932[see cross-cousin s.v. cross- B.]. 1937R. Stout Red Box iii. 38 Ortho-cousins are..the children of two brothers or of two sisters. 1972D. Davies Dict. Anthropol. 141 Ortho-Cousin, a term little used now,..can be a synonym for parallel cousin.. or for a parallel cousin of the same unilineal descent..group as the person concerned.
1891Taylor Elem. Geom. Conics iv. §31 The locus of the point of concourse of a pair of tangents at right angles will be shewn to be a circle, which we shall term the *Orthocycle. Note, It has also been named the Director Circle, since in the parabola it degenerates into the directrix and the line infinity.
1858Thudichum Urine 123 The *ortho-diagonal is shorter than the clino-diagonal. 1868Dana Min. Introd. (ed. 5) 27 The orthodiagonal section. 1879Rutley Stud. Rocks ix. 80 Sections lying in the zone of the orthodiagonal.
1937Fiopian Footprints VIII. 3/2 Let us hope that the history of *orthodigita will in time be replete with names of those who will..have illuminated Podiatry. 1939H. A. Budin in Jrnl. Exper. Podiatry I. 19 In his first lecture on this subject, delivered at a local society meeting in February 1934, the writer introduced some of the appliances and the technic which he had devised... For the purpose of designation of this newer phase of therapeusis, the author..chose the term Orthodigita... Orthodigita may be defined as the amelioration or correction, by non-surgical means, of toe deformities or malalignments.
Ibid. (heading), New and improved *orthodigital appliances in the non-surgical correction of deformities of the..toes. 1968Fisher & Whitney in F. Weinstein Princ. & Pract. Podiatry xii. 265/1 Although permanent orthodigital correction is sought in adults also,..the patient may need to wear the appliance continually in order to keep the toes in proper alignment. 1978Chiropodist XXXIII. 105 Although I personally favour the qualities (for most orthodigita) of KE 20 silicone rubber, I have found that Otoform provides..an inexpensive and effective method of introducing removable silicone appliances to patients.
1895Story-Maskelyne Crystallogr. §328 This variety of dome is termed the *ortho-dome, because, like the ortho-prisms, it has an ortho-symmetrical character.
1956Jrnl. Chem. Physics XXIV. 1239 (heading) Magnetic properties of a gadolinium *orthoferrite, GdFeO3, crystal. 1966McGraw-Hill Encycl. Sci. & Technol. V. 219/2 Many of the orthoferrites are strongly ferromagnetic at liquid helium temperatures. 1971Sci. Amer. June 83/2 The first magnetic materials found to have the desired properties for studying the new bubble technology were orthoferrites, a special class of ferrites with the chemical formula RFeO3, where R represents yttrium or one or more rare-earth elements. Samarium terbium orthoferrite is a good example.
1897Lancet 18 Sept. 738/1 It has been found by Dr. Einhorn and Dr. Heintz, of Munich, that the compound methylic ether of amidoxybenzoic acid is possessed of remarkable anæsthetic, or rather analgesic, properties when locally applied. To this substance the name of ‘*orthoform’ has been given. 1940F. R. Davison Synopsis Materia Medica xi. 383 Orthoform..has also been used in dentistry, nasal catarrh, hay fever, and in similar conditions. 1965Faulconer & Keys Foundations Anesthesiol. II. iv. 806 In the light of these considerations it is understandable that the Orthoform group anesthetizes better than the corresponding benzoyl combinations.
1874R. Bown Man. Bot. 418 The typical and orthodox method, which may be styled *Orthogamy, or direct (‘straight’) fertilisation.
1941*Orthogeosynclinal [see parageosyncline s.v. para-1 1]. 1945Bull. Geol. Soc. Amer. LVI. 1172 Marginal geosynclines gaining principal detritus from uplifts in orthogeosynclinal belts. 1975McGraw-Hill Yearbk. Sci. & Technol. 223/1 The orthogeosynclinal belts of Stille and Kay have come to be understood as an assemblage of crustal features related to continental shelf subsidence.
1936tr. H. Stille in Bull. Amer. Assoc. Petroleum Geologists XX. 853 Although the orogenic movements took place at the same time in different areas, they were strong (Alpine type) only in certain mobile belts which had developed as *orthogeosynclines. 1951Mem. Geol. Soc. Amer. XLVIII. 88 The later Devonian and Carboniferous are of argillite and graywacke when detritus could reach the subsiding structural basin from distant highlands of rocks laid in orthogeosynclines. 1968Orthogeosyncline [see foredeep s.v. fore- 5].
1877Fraser's Mag. XVI. 565 The discrepance between our orthography and our *orthoglossy gravely discourages foreigners.
1902*Orthogneiss [see paragneiss s.v. para-1 1]. 1932A. Harker Metamorphism xvii. 271 The more or less distinctly banded crystalline rocks which are conveniently styled orthogneisses (in contradistinction to paragneisses, which are highly metamorphosed sediments) attain in some countries a vast development. 1962Mineral. Abstr. XV. 553/2 Alkaline syenitic orthogneisses form a lenticular body 5 km in length in biotite gneisses in the Cevadais area, near Ouguela, Alto Alentejo, Portugal.
1937D. L. Gunn et al. in Nature 18 Dec. 1064/2 Variations in generalized, undirected, random locomotory activity..are kineses... We propose to divide kineses into (a) *ortho⁓kineses..variations in linear velocity (previously called simply kineses), [etc.]. 1940Fraenkel & Gunn Orientation of Animals ii. ii. 17 Woodlice aggregate in moist air..by means of an ortho-kinesis. 1971J. D. Carthy in J. E. Smith et al. Invertebr. Panorama xii. 251 This behaviour, consisting of changing rates of movement with different levels of stimulation, is known as an orthokinesis.
1958― Introd. Behaviour Invertebr. xii. 317 When the stones are beneath the surface..they [sc. chitons] do not tend to congregate by a simple *orthokinetic response. 1973Nature 16 Nov. 168/1 An orthokinetic effect may serve to influence adult movements, as their rate of progress over the reefs is almost certainly affected by the ease with which they can find adequate food and shelter from day⁓light.
1907Practitioner Apr. 530 The chief disadvantage of Goldscheider's *ortho-percussion is that it requires an absolutely silent room. 1916L. F. Barker Monographic Med. II. 499 In orthopercussion, the force of the blow is directed exactly perpendicular to the surface. 1966Lancet 31 Dec. 1469/1 The technique of percussion (ortho⁓percussion) of the patient's abdomen in order to recognise peritoneal irritation is shown.
1926Daily Colonist (Victoria, B.C.) 2 July 6/6 (Advt.), The genuine His Master's Voice Victrola is the only true *orthophonic. 1927Gramophone V. 309/2 The gramophone part of it contains an improved form of orthophonic horn. 1954Pei & Gaynor Dict. Linguistics 155 Orthophonic, relating to orthophony..; conformable with the standard or accepted rules of pronunciation. 1969John Edwards Mem. Foundation Q. V. ii. 81 This valuable discographic aid lists all Victor Recordings..starting with the introduction of the electrical ‘orthophonic’ recording system in February, 1925.
1845W. Russell (title) *Orthophony, or Vocal Culture, a Manual of elementary Exercises for the Cultivation of the Voice in Elocution. Ibid. p. xiii, The term orthophony is used to designate the art of cultivating the voice. The systematic cultivation of the vocal organs..is a branch of education for which our own language furnishes no appropriate designation. The compiler of this manual has ventured to adopt, as a term convenient for this purpose, the word orthophony—a modification of the corresponding French word ‘orthophonie’, used to designate the art of training the vocal organs. 1954Pei & Gaynor Dict. Linguistics 155 Orthophony, Correct pronunciation or articulation.
1886*Orthophoria [see exophoria s.v. exo-]. 1907J. H. Parsons Dis. Eye xxviii. 563 In cases of latent squint the position of rest is not orthophoria, with the visual axes parallel, but heterophoria, with some deviation of the axes. 1950F. H. Alder Physiol. Eye x. 386 It is unfortunate that the implication is frequently made that orthophoria is the normal condition and heterophoria an abnormal one. This is not true.
1888Arch. Ophthalm. XVII. 159 In the *orthophoric state the eyes are able to unite images when a prism of 2° to 3° is introduced with its base up or down before one of the eyes. 1954S. Duke-Elder Parsons' Dis. Eye (ed. 12) xxix. 483 Since the position of rest is usually one of slight divergence, few people are orthophoric and some degree of heterophoria is almost universal.
1965Photogrammetric Engin. XXXI. 223/1 Several stereo aerial models from test areas were successfully compiled into contour maps and *orthophotos. 1972McGraw-Hill Yearbk. Sci. & Technol. 245 The orthophoto, like any good map, allows the engineer to lay out a proposed highway with accurate scale, direction, and curvature.
1955Photogrammetric Engin. XXI. 529/2 Given an *orthophotograph, the engineer, surveyor, forester, geologist,..can correlate points imaged on the orthophotograph with points observed on the ground, and..can make direct measurements on the orthophotograph to determine distances between points. 1970J. A. Howard Aerial Photo-Ecol. xii. 136 No doubt orthophotographs will have a wide application in natural resource studies not requiring a stereoscopic examination.
1967Photogrammetric Engin. XXXIII. 274/1 The altitude contours derived from the height measured can then be added, along with any desired annotations, to form an accurate ‘*orthophotomap’ of the area of interest. 1974Geo Abstr. G. 520 The Topographic Division of the U.S. Geological Survey produces a series of orthophoto products ranging from separate photos for in-house use..to the multicoloured orthophotomap.
1890Cent. Dict., *Orthophyre. 1895A. Harker Petrol. viii. 102 The most usual type of orthoclase-porphyry (orthophyre of Rosenbusch) is exemplified by dykes and sills in the Carboniferous of Thuringia. 1930Peach & Horne Geol. Scotl. iv. 108 Examples of dykes of orthophyre occur on Sgonnan Mòr. 1947E. E. Wahlstrom Igneous Minerals & Rocks x. 301 Orthophyre is a porphyritic trachite consisting largely of orthoclase.
1895A. Harker Petrol. viii. 102 Other porphyrites have the ‘*orthophyric’ type of ground⁓mass (with short felspar-prisms), as in the porphyries. 1964G. A. Joplin Petrogr. Austral. Igneous Rocks v. 65 Most trachytes are porphyritic with phenocrysts of anorthoclase in an orthophyric and/or trachytic ground⁓mass.
1879Rutley Stud. Rocks x. 88 When the light falls obliquely either on the basal plane, the *ortho⁓pinakoid, or the hemidome of a monoclinic felspar.
1889Q. Jrnl. Geol. Soc. XLV. ii. 299 The Augite is almost colourless, and gives the usual eight-sided sections. Prismatic, *ortho- and clinopinacoidal cleavages are present.
[1920Svensk Bot. Tidskr. XIV. 301, I have in my material found the following numbers: 14, 21, 28, 35 and 42. Further, in some specimens, I met with numbers not being a multiple of 7 (anorthoploid forms).] 1932Proc. 6th Internat. Congr. Genetics II. 63 The ratios between *orthoploid and aneuploid gametes in the cases studied were found to be 1·4:1. 1937T. Dobzhansky Genetics & Origin of Species ix. 268 In a translocation heterozygote at least six classes of sex cells can be produced... Classes 1 and 2 carry normal gene complements..; 1 and 2 are termed regular or orthoploid. 1963Portugaliae Acta Biol. A. VII. 8 The unfortunate terms orthoploid and anorthoploid have been used in various senses also by more recent writers. Ibid. 9 There is no doubt that euploid and aneuploid should be maintained and orthoploid and anorthoploid definitely dropped.
1895Story-Maskelyne Crystallogr. §328 The vertical or *ortho-prism.., usually distinguished as the prism-form, the faces of which lie in the zone [100, 010].
1903Mineral. Mag. XIII. 374 Following Rinne, E. Düll..proposes the terms *ortho-pyroxene and klinopyroxene. 1940Amer. Mineralogist XXV. 282 Orthopyroxenes of plutonic igneous rocks normally show well developed diopsidic lamellae. 1963W. A. Deer et al. Rock-Forming Min. II. 33 Many orthopyroxenes can be distinguished from clinopyroxenes by their characteristic pink to green pleochroism. 1970Science 28 Aug. 866/2 (heading) Orthopyroxene-plagioclase fragments in the lunar soil from Apollo 12.
1890Cent. Dict., *Orthorhaphous. 1899D. Sharp in Cambr. Nat. Hist. VI. vii. 458 In the Mesozoic epoch the Order [sc. Diptera] is found as early as the Lias, the forms being exclusively Orthorrhaphous. 1946Nature 2 Nov. 636/2 Against the orthorrhaphous Diptera, ‘Gammexane’ shows a high degree of activity. 1961Orthorrhaphous [see cyclorrhaphous adj. s.v. cyclo- 1].
1892Dana Min. Introd. p. xxxi, *Ortho-pyramids. 1898Ibid. 101 The pyramids may be unit pyramids (hhl), orthopyramids, (hkl) when h >k, or clinopyramids, (hkl) when h
1831Encycl. Brit. (ed. 7) III. 468/2 *Orthostyle, any straight range of columns.
1956L. U. de Sitter Struct. Geol. i. 16 A later uplift, separated from the last orogenic paroxysmal phase by a period of erosion, is typical of *orthotectonic regions. 1969Earth & Planetary Sci. Lett. VI. 189 The orthotectonic orogens forming island arcs such as Japan lie entirely within ocean basins. 1969J. F. Dewey in M. Kay N. Atlantic xxiv. 309/1 Strata ranging in age from late Precambrian through early Ordovician constitute a northern orthotectonic belt, characterized by complex recumbent and commonly triclinic fold geometry and high-grade metamorphism.
1921Jrnl. Exper. Zool. XXXII. 7 Limb bud placed in natural location—*orthotopic transplantation. 1958Immunology I. 46 The survival times of successive sets of orthotopic scale (skin) homografts revealed that increasing systematic immunity develops rapidly in stepwise fashion. 1968National Observer (U.S.) 29 Jan. 4/4 Dr. Starzl performed the first orthotopic liver transplant, in which the diseased liver is removed and another implanted, in 1963.
1921Jrnl. Exper. Zool. XXXII. 61 The shoulder-girdle in *orthotopically grafted limbs is derived in part from the host and in part from the transplanted tissue. 1974Nature 11 Oct. 553/1 When solid tissue allografts are transplanted orthotopically to alien hosts they are rejected with a characteristic tempo and vigour that depends primarily on the immunogenetic disparity between donor and host. 1976Ibid. 22 Jan. 209/1 We used a standardised H-test procedure in which tail-skin grafts were orthotopically exchanged in a ‘reciprocal circle’ among syngeneic mice.
18..Shepard cited by Webster (1864) for *Orthotypous.
1967M. E. J. Young Radiological Physics (ed. 2) xi. 372 Superficial therapy..60–120 kVp. Medium voltage therapy... 120–140 kVp. Deep therapy or *orthovoltage therapy..200–400 kVp. Megavoltage therapy... Above 1 MV. 1972Barnes & Rees Conc. Textbk. Radiotherapy iii. 63 In recent years there has been a tendency for deep X-ray therapy (orthovoltage radiation) to be largely superseded by megavoltage therapy as the advantages of the higher energy radiation become more generally appreciated. 1976Lancet 6 Nov. 1031/2 All patients received induction treatment..for 4 weeks followed by 2400 rad of orthovoltage cranial irradiation plus five intrathecal injections of methotrexate.
1966B. V. Derjaguin in Discussions Faraday Soc. XLII. 118 The usual state of water and certain other liquids is thermodynamically metastable... It would be convenient to call ‘usual water’ metawater, and the anomalous columns—*orthowater. 1969Nature 27 Dec. 1293/1 Water condensed into glass or quartz capillaries has unusual properties, which have been ascribed to the formation of a new polymer termed ‘orthowater’, ‘anomalous’ water or ‘polywater’. 1970Compton Yearbk. 176/2 The substance, variously called orthowater, anomalous water, polywater, and super⁓water, differs radically from ordinary water.
2. In Chemistry.
a. Ortho- is used to distinguish one class of acids and their salts from another denoted by the prefix meta-, which contain the same elements in different proportions, the meta- acid containing a molecule of H2O less than the ortho- acid, the ortho- salt being also the more basic and the meta- salt the less basic. Thus orthophosphoric acid H3PO4, metaphosphoric acid HPO3; sodium orthophosphate Na3PO4, sodium metaphosphate NaPO3. So orthosilicic, orthotungstic, orthosilicate, orthotungstate, etc. This use of ortho- originated with Prof. Odling in 1859, meta- having been introduced by Graham in 1833.
b. With the names of isomeric benzene di-derivatives, ortho- is applied to those in which two consecutive hydrogen atoms are replaced by another element or radical, as distinguished from meta- and para- derivatives, in which the two atoms are not consecutive, but unsymmetrically or symmetrically dispersed respectively. Examples: orthodibromobenzene, orthobromotoluene, orthopropylphenol; orthoˈxylene, an isomer of xylene that is a colourless mobile liquid and is now obtained from petroleum naphtha for use esp. as a source of phthalic anhydride. (This was introduced by Körner, 1867, in Brussels Acad. Sc. Bull. XXIV. 166–185.)
As ortho-, although usually prefixed without a hyphen, has always its own distinct meaning, chemical names in ortho- are not separately treated in this Dictionary.
1859Odling in L.E. & D. Philos. Mag. Ser. iv. XXVII. 368 On Ortho- and Meta-silicates. Intermediate between common or orthophosphates and metaphosphates we have several varieties of compounds, among which the best defined are the pyrophosphates, salts which result from the union of an atom of orthophosphate with an atom of metaphosphate. 1868Watts Dict. Chem. IV. 238 The prefixes ortho- and meta- have been introduced..to denote two classes of salts..the more basic salts being called ortho- and the less basic, meta- salts. 1872Jrnl. Chem. Soc. XXV. 893 (heading) Preparation of orthoxylene from liquid bromotoluene. 1873Watts Fownes' Chem. (ed. 11) 225 The aqueous solution..deposits orthophosphoric acid in prismatic crystals. 1876Harley Mat. Med. (ed. 6) 66 Neutral solutions of the orthophosphates..give precipitates with salts of lime and baryta. 1877Watts Fownes' Chem. II. 422 The di-derivatives of benzene..exhibit three such modifications which are distinguished by the prefixes ortho, meta, and para: thus..Orthodichlorobenzene, 1:2, C6ClClHHHH, Metadichlorobenzene, 1:3, C6ClHClHHH; Paradichlorobenzene, 1:4, C6ClHHClHH. 1968Economist 14 Dec. 63/3 Both BP Chemicals and ICI have existing plants for phthalic anhydride. ICI's 20,000 ton plant at Wilton manufactures from naphthalene, an older method being replaced by the ortho-xylene method as oil supersedes coal tar as a source of raw materials for the chemical industry.
3. Physics and Chem. Of, pertaining to, or designating the form of some homonuclear diatomic molecules in which (as in orthohydrogen) the two nuclei have parallel spins (see also quot. 19402); also more widely, characterized by the presence of parallel spins. Also as an independent word.
1927T. Verschoyle tr. Haas's Atomic Theory v. 182 No spectroscopic transition between the normal para⁓term and the lowest (two-quantum) ortho-term is possible. 1939J. W. T. Spinks tr. Herzberg's Molecular Spectra I. iii. 150 The modification with the greater statistical weight is usually called the ortho modification and that with the smaller weight the para modification. 1940Glasstone Text-bk. Physical Chem. i. 79 From the spectrum of helium it is known that the ortho-levels have less energy than the par-levels with the same values of the quantum numbers n and l. Ibid. 96 Symmetrical polyatomic molecules, such as water, deuterium oxide, cyanogen and acetylene, exist in ortho- and para-forms; they behave in a manner similar to hydrogen, deuterium and nitrogen molecules, since the other atoms, viz., carbon and oxygen, have no nuclear spins. 1966D. H. Whiffen Spectroscopy ix. 114 The best-known example is hydrogen where the ortho states with odd J have three times the degeneracy of the even J or para states. 1970P. J. Wheatley Chem. Consequences Nucl. Spin xi. 50 The hydrogen molecule, 1H2... The rotation levels with J odd are associated with symmetric nuclear states, that is with ortho states, and..the rotational levels with J even are associated with antisymmetric nuclear states, that is with para states. Ibid. 51 The deuterium molecule, 2D2... Ortho-D2 will be associated with rotational levels having even values of J, and para-D2 with those having odd values of J. 1977Sci. Amer. Oct. 66/3 The parallel quark spins combine to give each meson one unit of spin. This arrangement of spins is known in atomic physics as the ‘ortho’ configuration. |