omegan.adj.

Brit.

/ˈəʊmᵻɡə/,

/əʊˈmiːɡə/,

/əʊˈmɛɡə/,

/əʊˈmeɪɡə/, U.S.

/oʊˈmeɪɡə/,

/oʊˈmɛɡə/

Origin: Of multiple origins. Partly a borrowing from Latin. Partly a borrowing from Greek. Etymons: Latin omega; Greek ω μέγα.

Etymology: < post-classical Latin omega (see note) and its etymon Hellenistic Greek ω μέγα, lit. ‘great O’ (as opposed to ο μικρόν little O, omicron n.) < ancient Greek ω , the letter representing a long o (see O n.¹) + μέγα , neuter of μέγας (see mega- comb. form). Compare Middle French, French omega the end, the final development (12th cent. in Old French), last letter of the Greek alphabet (1558).Greek ω μέγα and ο μικρόν both appear in Herodian Grammaticus (2nd cent. a.d.). It is unclear at what date Greek scribes first treated these phrases as single words (which may be indicated by a breathing over the initial letter together with the absence of a second accent). Post-classical Latin omega is first recorded in Christian writers of the 5th cent., but until the 11th cent. is restricted to quotations from Revelation. The development of a distinctive letter for a long o in ancient Greek appears to have occurred in Ionic c600 b.c. The alleged Middle English example from Mandeville's Travels given in N.E.D. (1902) s.v. from an 18th-century edition is not supported by more recent editions from the same, unique manuscript of this version of the text.

A. n.

I. The letter.

a. The last of a series; the end, the final development; the last word. Chiefly in contrast with alpha, esp. in alpha and omega n. at alpha n. 2.

ΚΠ

a1398 J. Trevisa tr. Bartholomaeus Anglicus De Proprietatibus Rerum (BL Add.) f. 326^v Oure lord Crist, god þat is Alpha & omega, endynge and bygynnynge.

1567 G. Turberville Of Renowmed Lady l. 15, in Epitaphes, Epigrams, Songs & Sonets You Alpha were when I this Booke begoonne And formost, as became your state, did stande, To be Omega now you will not shoonne, (O Noble Dame) I trust.

1607 B. Barnes Divils Charter v. vi The most all potent maker of all things, The Alpha and Omega of all bountie.

1651 N. Bacon Contin. Hist. Disc. Govt. 225 Formerly the Pope usurped the power to be the Omega to the resolves of all Councills.

1766 W. Falconer Demagogue 24 The idol of the mob, behold him stand, The Alpha and Omega of the land!

a1821 J. Keats Hyperion (new ed.) 14 in Misc. Philobiblon Soc. (1856–7) III The pale Omega of a wither'd race.

1842 Ld. Tennyson Two Voices in Poems (new ed.) II. 134 ‘Omega! thou art Lord,’ they said, ‘We find no motion in the dead.’

1886 Athenæum 25 Dec. 863/3 These two volumes may be considered as the omega of Hebrew bibliography.

1925 V. Lindsay Johnny Appleseed's Hymn to Sun in Coll. Poems liv Come quickly, Alpha, Omega, Our God, the beginning and end!

1997 G. S. Helfman et al. Diversity of Fishes xxi. 373/1 In linear hierarchies, an alpha animal dominates all others, a beta animal is subordinate to the alpha..and so on, down to the last, or omega, individual.

b. = Omega point n. 1.

ΘΚΠ

the mind > mental capacity > philosophy > theoretical scientific philosophy > [noun] > philosophy of Teilhard de Chardin

Omega point1959

omega1960

Teilhardian1970

1959 B. Wall tr. T. de Chardin Phenomenon of Man iv. ii. 259 Accordingly its enormous layers, followed in the right direction, must somewhere ahead become involuted to a point which we might call Omega, which fuses and consumes them integrally in itself.]

1960 Amer. Midland Naturalist 63 256 A synthesis of the emergence of life which will culminate in the sharing of all life in the Omega, which is the end point of evolution.

1986 Amer. Scholar 65 486 Human history has a meaning and a purpose, a telos, or, as Teilhard de Chardin expressed it, an alpha and an omega.

2. (The name of) the last letter (Ω, ω) of the Greek alphabet.In transliterating ancient Greek, usually rendered as o (in ancient Greek used to distinguish a long from a short o sound: cf. omicron n. 1).

ΘΚΠ

the world > relative properties > order > order, sequence, or succession > end or conclusion > [noun]

endc1000

endingc1000

finea1300

conclusion1382

ooc1384

close1399

finance1449

terminationc1500

last?1520

winding up1560

wind-up1573

wind-up-all1573

conclusure1578

clause1581

upshot1582

desinence1598

omega1599

Godspeed1606

finis1682

finale1786

finish1790

tie-up1829

Z1877

curtains1912

taps1917

society > communication > writing > written character > name of written character > [noun] > Greek

alphac1175

muc1175

betaa1400

taua1400

chic1400

deltac1400

etac1400

kappac1400

gamma?a1425

lambda?a1425

nu?a1425

phi?a1425

pi?a1425

psi?a1425

rho?a1425

xi?a1425

zeta?a1425

upsilon1559

san1584

omega1599

theta1603

iota1607

sigma1607

omicron1631

digamma1699

epsilon1842

zeta1850

1574 J. Baret Aluearie O Introd. sig. Ll.iii The Greekes therefore haue ωμικρον standing for a short o: and ωμεγα for this double or long o, oo.]

1599 First Bk. Preseruation Henry VII Ep. to Queen sig. F4^v As two Greeke letters in Grecian Alphabet, Alpha, First letter plaste is; but placed last is Omega.

1640 S. Daines Orthoepia Anglicana 12 Oo in Poore imitates in sound the Greek Omega.

1728 E. Chambers Cycl. at O The Greeks had two O's, viz. Omicron, ο, and Omega ω.

1783 T. Holcroft Human Happiness i. 2 Tho' no great scholar, knew your Greek A, Alpha, and so forth, to Omega.

1833 Philos. Trans. (Royal Soc.) 123 461 (table) A most curious object, not unlike the nebula in Orion (as it used to be figured, like a Greek capital omega).

1897 T. C. Allbutt et al. Syst. Med. III. 815 The outline of such a loop is that of a capital omega.

1930 E. A. Robinson Coll. Poems (1937) 1051 Two Alphas, And a malevolent long alphabet Between them and Omega.

1947 Jrnl. Investigative Dermatol. 9 213 Many such Greek verb stems..end in o represented by omicron when the pronunciation is short (ŏ) or by omega (ω) when it is long (ō).

1992 N.Y. Rev. Bks. 5 Mar. 56/3 Certain letters called ‘supplementals’—phi, chi, psi, omega—had different values in different places.

3. Astronomy. Used in the name of the 24th star of a constellation (in some cases subsequently identified as an object other than a star). Frequently written ω.The use of Greek letters to designate the stars in a constellation was introduced by J. Bayer in his Uranometria (1603). There is an approximate correspondence between the ordinal positions of the stars in this series and their brightness.

ΚΠ

1754 J. Hill Urania at A Where the number of the stars in a constellation is greater than the number of letters in the Greek alphabet, he [sc. Bayer] has recourse to the Roman,..beginning after the Greek omega with the Roman A.

1796 W. Herschel in Philos. Trans. (Royal Soc.) 86 200 (table) Lustre of the stars in Capricornus... ω 6.

1898 Science 23 Sept. 391/1 The shortest period variable so far discovered..is a small star in the great southern cluster Omega Centauri.

1902 S. I. Bailey (title) A discussion of variable stars in the cluster ω Centauri.

1998 Mod. Astronomer Mar. 14/1 Inhabitants around the star Omega 1 Scorpii, another G2 star some 272 light-years away, are in the path of the Madley-1 beam.

II. Symbolic uses.

4. Particle Physics.

a. (Written Ω.) Any of various hyperons (see note below). disused.The decay schemes in quot. 1953 are those of the sigma (Σ) particles, whilst the mass specified in quot. 1954² (and elsewhere) is that of the xi minus. In quot. 1954¹ a lambda particle is referred to.

ΘΚΠ

the world > matter > physics > atomic physics > particle physics > particle participating in strong interaction > baryon > [noun] > hyperon

V1950

hyperon1953

omega1953

1953 Nuovo Cimento 10 1741 Two decay schemes have been proposed by analogy with the decay of V₁⁰-particles. Adopting the nomenclature proposed at the Bagnères Conference these are: (a) Ω_π^± → n + π^± + Q, (b) Ω_p⁺ → p + π⁰ + Q.

1954 Sci. News 31 62 Ω⁰-particle. Mass, 2,184 ± 7 [≡ 1116 MeV]. Lifetime, (3·3 ± 1) × 10⁻¹⁰ seconds... Decay scheme: Ω⁰ → p⁺ + π⁻.

1954 Physical Rev. 96 543/1 The known hyperons, Λ⁻, Ω⁻, have masses equivalent to 1200 and 1320 Mev, respectively.

b. In full omega meson. A neutral meson with a mass of 782 MeV that is observed as a resonance when protons and antiprotons of sufficient energy collide, and on decaying typically produces a positive, a negative, and a neutral pion. Frequently written ω.The omega meson has zero strangeness, zero isospin, unit spin, and negative parity.

ΘΚΠ

the world > matter > physics > atomic physics > particle physics > particle participating in strong interaction > meson > [noun] > type of

tau1949

photomeson1950

theta1954

eta1961

omega meson1961

rho1961

phi meson1962

bottomonium1976

quarkonium1977

upsilon1977

1961 B. C. Maglić et al. in Physical Rev. Lett. 7 178/1 The existence of a heavy neutral meson with T = 0 and J = 1⁻ was predicted by Nambu... Such a particle is also expected in the vector meson theory of Sakurai and..according to the unitary symmetry theory; and for other reasons. We will refer to it as ω.

1961 New Scientist 5 Oct. 48/1 Four physicists at the Lawrence Radiation Laboratory, Berkeley, have made observations..that appear to indicate unequivocally the presence, in a proton-antiproton reaction, of the omega-meson.

1971 Sci. Amer. July 100/2 Three vector mesons with zero strangeness are currently known: the rho, the omega and the phi.

1997 Physics Lett. B. 411 362 We have measured the branching ratio for the radiative decay ω → η γ with ω mesons produced in antiproton-proton annihilation at rest into π⁰ ω and η ω.

2000 Jrnl. Physics A 33 8305 We theoretically predict the phenomenological coupling constant of the ω meson, which mediates the short range and repulsive nucleon force.

c. In full omega minus. A negatively charged hyperon with a mass of 1672 MeV that decays via the weak interaction into either a xi particle and a pion or a lambda particle and a kaon. Frequently written Ω⁻.The omega minus has strangeness of −3, zero isospin, spin of 3/2, and positive parity. It was predicted by the theory of the eightfold way, and its discovery in 1964 was important in the development of the concept of quarks.

ΘΚΠ

the world > matter > physics > atomic physics > particle physics > particle participating in strong interaction > baryon > [noun] > hyperon > negatively charged

omega minus1962

1962 M. Gell-Mann in Proc. Internat. Conf. High-energy Physics 805/2 Starting with the resonance at 1238 MeV, we may conjecture that the Y₁*, at 1385 MeV and the Ξ* at 1535 MeV might belong to this supermultiplet... If J = 3/2⁺ is really right for these two cases, then our speculation might have some value and we should look for the last particle, called, say, Ω⁻ with S = −3, I = 0.

1964 Physical Rev. Lett. 12 204/1 The multitude of resonances which have been discovered recently..can be arranged as a decuplet with one member still missing... This particle (which we shall call Ω⁻, following Gell-Mann) is predicted to be a negatively charged isotopic singlet with strangeness minus three.

1964 Listener 30 Apr. 711/1 The new theory [of unitary symmetry] has made one striking prediction which was subsequently found to be correct: the observation of the negatively charged Omega particle.

1972 Daily Colonist (Victoria, Brit. Columbia) 24 Feb. 5/2 The physicists hope to make the first observation of ‘quarks’..by studying the activity of a rare and elusive sub-atomic particle called the omega-minus.

1974 H. Frauenfelder & E. M. Henley Subatomic Physics i. 6 The negative kaon..collides with a proton and produces a positive kaon, a neutral kaon, and an omega minus. The Ω⁻ decays into a Ξ⁰ and a π⁻.

1993 N.Y. Rev. Bks. 21 Oct. 78/3 The Higgs is not to be just another of the long list of successfully predicted particles, like the positron, omega-minus, neutrino, anti-proton, or tau-particle.

5. Astronomy. The ratio of the actual density of the universe to the critical density that corresponds to an infinite flat universe; also called density parameter.A value of omega greater than one corresponds to a closed universe that will eventually stop expanding and start contracting. A value of omega less than one corresponds to an open universe that will expand indefinitely (cf. open adj. 19c).

ΚΠ

1976 Astrophysical Jrnl. 203 569/2 In order that the X-ray emission from the cluster not exceed the observed values, their results showed that the density parameter Ω ≪ 0.2.

1987 Nature 19 Nov. 294/3 The efforts by astronomers to solve the omega problem—the question of whether the Universe is open and will expand forever.

1995 New Scientist 19 Aug. 43/1 The question of whether the Universe will end in fire or ice becomes the question: is omega greater or less than unity?

1998 Science 30 Jan. 651/2 Because both mass and energy can curve space-time,..a flat universe has to contain a specific density of mass-energy. Known as an omega of 1, that density—if it all takes the form of mass—would be just enough to halt cosmic expansion after an infinite time.

B. adj.

Art. In the style of or belonging to the Omega Workshop. Cf. Omega Workshop n.

ΘΚΠ

society > leisure > the arts > visual arts > period, movement, or school of art > late 19th and 20th centuries > [adjective] > others

all'antica1605

neo-Gothic1878

Barbizon1890

chinoiserie1909

neoprimitive1922

omega1922

Suprematist1922

beaux arts1924

ashcan1934

vitalistic1937

Euston Road1941

precisionist1943

abstract impressionist1950

abstract-concrete1955

neo-expressionist1957

metaphysical1958

structurist1958

auto-destructive1959

Rayonist1968

post-minimal1971

assemblagist1977

Neo-Geo1987

1922 D. H. Lawrence Aaron's Rod (N.Y. ed.) iii. 32 Into this reticence pieces of futurism, Omega cushions and Van-Gogh-like pictures exploded their colours.

1970 Oxf. Compan. Art 790/2 The Omega artists believed that the creative joy of the artist and craftsman should go into the making of articles for everyday use.

1973 Guardian 22 Jan. 8/1 The dining-room's Omega chairs attend its round painted table.

1986 New Yorker 18 Aug. 66/3 People said that the Omega furniture always fell to bits, but these chairs have stood up to the wear and tear of Bell family life pretty well.

Compounds

C1. Similative (in sense A. 2).

omega-shaped adj.

ΚΠ

1858 Househ. Words 4 Dec. 6/1 I look for the omega-shaped palm.

1991 Saudi Med. Jrnl. 12 62/2 The epiglottis is omega-shaped and floppy.

C2.

omega-form n. a shape resembling the Greek letter omega.

ΚΠ

1880 Mrs. J. H. Gray Fourteen Months in Canton xxviii. 301 They are always in the Omega or horse-shoe form.

1959 M. Freeman Chinese Family & Marriage in Singapore vii. 206 Among all Chinese in Malaya..the omega-form is expressed [in tomb design] wherever possible by having an oval-brick border round the mound and projecting wings at the end.

This entry has been updated (OED Third Edition, March 2004; most recently modified version published online March 2022).

单词	omega
释义	omegan.adj. Brit. /ˈəʊmᵻɡə/, /əʊˈmiːɡə/, /əʊˈmɛɡə/, /əʊˈmeɪɡə/, U.S. /oʊˈmeɪɡə/, /oʊˈmɛɡə/ Origin: Of multiple origins. Partly a borrowing from Latin. Partly a borrowing from Greek. Etymons: Latin omega; Greek ω μέγα. Etymology: < post-classical Latin omega (see note) and its etymon Hellenistic Greek ω μέγα, lit. ‘great O’ (as opposed to ο μικρόν little O, omicron n.) < ancient Greek ω , the letter representing a long o (see O n.¹) + μέγα , neuter of μέγας (see mega- comb. form). Compare Middle French, French omega the end, the final development (12th cent. in Old French), last letter of the Greek alphabet (1558).Greek ω μέγα and ο μικρόν both appear in Herodian Grammaticus (2nd cent. a.d.). It is unclear at what date Greek scribes first treated these phrases as single words (which may be indicated by a breathing over the initial letter together with the absence of a second accent). Post-classical Latin omega is first recorded in Christian writers of the 5th cent., but until the 11th cent. is restricted to quotations from Revelation. The development of a distinctive letter for a long o in ancient Greek appears to have occurred in Ionic c600 b.c. The alleged Middle English example from Mandeville's Travels given in N.E.D. (1902) s.v. from an 18th-century edition is not supported by more recent editions from the same, unique manuscript of this version of the text. A. n. I. The letter. 1. a. The last of a series; the end, the final development; the last word. Chiefly in contrast with alpha, esp. in alpha and omega n. at alpha n. 2. ΚΠ a1398 J. Trevisa tr. Bartholomaeus Anglicus De Proprietatibus Rerum (BL Add.) f. 326^v Oure lord Crist, god þat is Alpha & omega, endynge and bygynnynge. 1567 G. Turberville Of Renowmed Lady l. 15, in Epitaphes, Epigrams, Songs & Sonets You Alpha were when I this Booke begoonne And formost, as became your state, did stande, To be Omega now you will not shoonne, (O Noble Dame) I trust. 1607 B. Barnes Divils Charter v. vi The most all potent maker of all things, The Alpha and Omega of all bountie. 1651 N. Bacon Contin. Hist. Disc. Govt. 225 Formerly the Pope usurped the power to be the Omega to the resolves of all Councills. 1766 W. Falconer Demagogue 24 The idol of the mob, behold him stand, The Alpha and Omega of the land! a1821 J. Keats Hyperion (new ed.) 14 in Misc. Philobiblon Soc. (1856–7) III The pale Omega of a wither'd race. 1842 Ld. Tennyson Two Voices in Poems (new ed.) II. 134 ‘Omega! thou art Lord,’ they said, ‘We find no motion in the dead.’ 1886 Athenæum 25 Dec. 863/3 These two volumes may be considered as the omega of Hebrew bibliography. 1925 V. Lindsay Johnny Appleseed's Hymn to Sun in Coll. Poems liv Come quickly, Alpha, Omega, Our God, the beginning and end! 1997 G. S. Helfman et al. Diversity of Fishes xxi. 373/1 In linear hierarchies, an alpha animal dominates all others, a beta animal is subordinate to the alpha..and so on, down to the last, or omega, individual. b. = Omega point n. 1. ΘΚΠ the mind > mental capacity > philosophy > theoretical scientific philosophy > [noun] > philosophy of Teilhard de Chardin Omega point1959 omega1960 Teilhardian1970 1959 B. Wall tr. T. de Chardin Phenomenon of Man iv. ii. 259 Accordingly its enormous layers, followed in the right direction, must somewhere ahead become involuted to a point which we might call Omega, which fuses and consumes them integrally in itself.] 1960 Amer. Midland Naturalist 63 256 A synthesis of the emergence of life which will culminate in the sharing of all life in the Omega, which is the end point of evolution. 1986 Amer. Scholar 65 486 Human history has a meaning and a purpose, a telos, or, as Teilhard de Chardin expressed it, an alpha and an omega. 2. (The name of) the last letter (Ω, ω) of the Greek alphabet.In transliterating ancient Greek, usually rendered as o (in ancient Greek used to distinguish a long from a short o sound: cf. omicron n. 1). ΘΚΠ the world > relative properties > order > order, sequence, or succession > end or conclusion > [noun] endc1000 endingc1000 finea1300 conclusion1382 ooc1384 close1399 finance1449 terminationc1500 last?1520 winding up1560 wind-up1573 wind-up-all1573 conclusure1578 clause1581 upshot1582 desinence1598 omega1599 Godspeed1606 finis1682 finale1786 finish1790 tie-up1829 Z1877 curtains1912 taps1917 society > communication > writing > written character > name of written character > [noun] > Greek alphac1175 muc1175 betaa1400 taua1400 chic1400 deltac1400 etac1400 kappac1400 gamma?a1425 lambda?a1425 nu?a1425 phi?a1425 pi?a1425 psi?a1425 rho?a1425 xi?a1425 zeta?a1425 upsilon1559 san1584 omega1599 theta1603 iota1607 sigma1607 omicron1631 digamma1699 epsilon1842 zeta1850 1574 J. Baret Aluearie O Introd. sig. Ll.iii The Greekes therefore haue ωμικρον standing for a short o: and ωμεγα for this double or long o, oo.] 1599 First Bk. Preseruation Henry VII Ep. to Queen sig. F4^v As two Greeke letters in Grecian Alphabet, Alpha, First letter plaste is; but placed last is Omega. 1640 S. Daines Orthoepia Anglicana 12 Oo in Poore imitates in sound the Greek Omega. 1728 E. Chambers Cycl. at O The Greeks had two O's, viz. Omicron, ο, and Omega ω. 1783 T. Holcroft Human Happiness i. 2 Tho' no great scholar, knew your Greek A, Alpha, and so forth, to Omega. 1833 Philos. Trans. (Royal Soc.) 123 461 (table) A most curious object, not unlike the nebula in Orion (as it used to be figured, like a Greek capital omega). 1897 T. C. Allbutt et al. Syst. Med. III. 815 The outline of such a loop is that of a capital omega. 1930 E. A. Robinson Coll. Poems (1937) 1051 Two Alphas, And a malevolent long alphabet Between them and Omega. 1947 Jrnl. Investigative Dermatol. 9 213 Many such Greek verb stems..end in o represented by omicron when the pronunciation is short (ŏ) or by omega (ω) when it is long (ō). 1992 N.Y. Rev. Bks. 5 Mar. 56/3 Certain letters called ‘supplementals’—phi, chi, psi, omega—had different values in different places. 3. Astronomy. Used in the name of the 24th star of a constellation (in some cases subsequently identified as an object other than a star). Frequently written ω.The use of Greek letters to designate the stars in a constellation was introduced by J. Bayer in his Uranometria (1603). There is an approximate correspondence between the ordinal positions of the stars in this series and their brightness. ΚΠ 1754 J. Hill Urania at A Where the number of the stars in a constellation is greater than the number of letters in the Greek alphabet, he [sc. Bayer] has recourse to the Roman,..beginning after the Greek omega with the Roman A. 1796 W. Herschel in Philos. Trans. (Royal Soc.) 86 200 (table) Lustre of the stars in Capricornus... ω 6. 1898 Science 23 Sept. 391/1 The shortest period variable so far discovered..is a small star in the great southern cluster Omega Centauri. 1902 S. I. Bailey (title) A discussion of variable stars in the cluster ω Centauri. 1998 Mod. Astronomer Mar. 14/1 Inhabitants around the star Omega 1 Scorpii, another G2 star some 272 light-years away, are in the path of the Madley-1 beam. II. Symbolic uses. 4. Particle Physics. a. (Written Ω.) Any of various hyperons (see note below). disused.The decay schemes in quot. 1953 are those of the sigma (Σ) particles, whilst the mass specified in quot. 1954² (and elsewhere) is that of the xi minus. In quot. 1954¹ a lambda particle is referred to. ΘΚΠ the world > matter > physics > atomic physics > particle physics > particle participating in strong interaction > baryon > [noun] > hyperon V1950 hyperon1953 omega1953 1953 Nuovo Cimento 10 1741 Two decay schemes have been proposed by analogy with the decay of V₁⁰-particles. Adopting the nomenclature proposed at the Bagnères Conference these are: (a) Ω_π^± → n + π^± + Q, (b) Ω_p⁺ → p + π⁰ + Q. 1954 Sci. News 31 62 Ω⁰-particle. Mass, 2,184 ± 7 [≡ 1116 MeV]. Lifetime, (3·3 ± 1) × 10⁻¹⁰ seconds... Decay scheme: Ω⁰ → p⁺ + π⁻. 1954 Physical Rev. 96 543/1 The known hyperons, Λ⁻, Ω⁻, have masses equivalent to 1200 and 1320 Mev, respectively. b. In full omega meson. A neutral meson with a mass of 782 MeV that is observed as a resonance when protons and antiprotons of sufficient energy collide, and on decaying typically produces a positive, a negative, and a neutral pion. Frequently written ω.The omega meson has zero strangeness, zero isospin, unit spin, and negative parity. ΘΚΠ the world > matter > physics > atomic physics > particle physics > particle participating in strong interaction > meson > [noun] > type of tau1949 photomeson1950 theta1954 eta1961 omega meson1961 rho1961 phi meson1962 bottomonium1976 quarkonium1977 upsilon1977 1961 B. C. Maglić et al. in Physical Rev. Lett. 7 178/1 The existence of a heavy neutral meson with T = 0 and J = 1⁻ was predicted by Nambu... Such a particle is also expected in the vector meson theory of Sakurai and..according to the unitary symmetry theory; and for other reasons. We will refer to it as ω. 1961 New Scientist 5 Oct. 48/1 Four physicists at the Lawrence Radiation Laboratory, Berkeley, have made observations..that appear to indicate unequivocally the presence, in a proton-antiproton reaction, of the omega-meson. 1971 Sci. Amer. July 100/2 Three vector mesons with zero strangeness are currently known: the rho, the omega and the phi. 1997 Physics Lett. B. 411 362 We have measured the branching ratio for the radiative decay ω → η γ with ω mesons produced in antiproton-proton annihilation at rest into π⁰ ω and η ω. 2000 Jrnl. Physics A 33 8305 We theoretically predict the phenomenological coupling constant of the ω meson, which mediates the short range and repulsive nucleon force. c. In full omega minus. A negatively charged hyperon with a mass of 1672 MeV that decays via the weak interaction into either a xi particle and a pion or a lambda particle and a kaon. Frequently written Ω⁻.The omega minus has strangeness of −3, zero isospin, spin of 3/2, and positive parity. It was predicted by the theory of the eightfold way, and its discovery in 1964 was important in the development of the concept of quarks. ΘΚΠ the world > matter > physics > atomic physics > particle physics > particle participating in strong interaction > baryon > [noun] > hyperon > negatively charged omega minus1962 1962 M. Gell-Mann in Proc. Internat. Conf. High-energy Physics 805/2 Starting with the resonance at 1238 MeV, we may conjecture that the Y₁, at 1385 MeV and the Ξ at 1535 MeV might belong to this supermultiplet... If J = 3/2⁺ is really right for these two cases, then our speculation might have some value and we should look for the last particle, called, say, Ω⁻ with S = −3, I = 0. 1964 Physical Rev. Lett. 12 204/1 The multitude of resonances which have been discovered recently..can be arranged as a decuplet with one member still missing... This particle (which we shall call Ω⁻, following Gell-Mann) is predicted to be a negatively charged isotopic singlet with strangeness minus three. 1964 Listener 30 Apr. 711/1 The new theory [of unitary symmetry] has made one striking prediction which was subsequently found to be correct: the observation of the negatively charged Omega particle. 1972 Daily Colonist (Victoria, Brit. Columbia) 24 Feb. 5/2 The physicists hope to make the first observation of ‘quarks’..by studying the activity of a rare and elusive sub-atomic particle called the omega-minus. 1974 H. Frauenfelder & E. M. Henley Subatomic Physics i. 6 The negative kaon..collides with a proton and produces a positive kaon, a neutral kaon, and an omega minus. The Ω⁻ decays into a Ξ⁰ and a π⁻. 1993 N.Y. Rev. Bks. 21 Oct. 78/3 The Higgs is not to be just another of the long list of successfully predicted particles, like the positron, omega-minus, neutrino, anti-proton, or tau-particle. 5. Astronomy. The ratio of the actual density of the universe to the critical density that corresponds to an infinite flat universe; also called density parameter.A value of omega greater than one corresponds to a closed universe that will eventually stop expanding and start contracting. A value of omega less than one corresponds to an open universe that will expand indefinitely (cf. open adj. 19c). ΚΠ 1976 Astrophysical Jrnl. 203 569/2 In order that the X-ray emission from the cluster not exceed the observed values, their results showed that the density parameter Ω ≪ 0.2. 1987 Nature 19 Nov. 294/3 The efforts by astronomers to solve the omega problem—the question of whether the Universe is open and will expand forever. 1995 New Scientist 19 Aug. 43/1 The question of whether the Universe will end in fire or ice becomes the question: is omega greater or less than unity? 1998 Science 30 Jan. 651/2 Because both mass and energy can curve space-time,..a flat universe has to contain a specific density of mass-energy. Known as an omega of 1, that density—if it all takes the form of mass—would be just enough to halt cosmic expansion after an infinite time. B. adj. Art. In the style of or belonging to the Omega Workshop. Cf. Omega Workshop n. ΘΚΠ society > leisure > the arts > visual arts > period, movement, or school of art > late 19th and 20th centuries > [adjective] > others all'antica1605 neo-Gothic1878 Barbizon1890 chinoiserie1909 neoprimitive1922 omega1922 Suprematist1922 beaux arts1924 ashcan1934 vitalistic1937 Euston Road1941 precisionist1943 abstract impressionist1950 abstract-concrete1955 neo-expressionist1957 metaphysical1958 structurist1958 auto-destructive1959 Rayonist1968 post-minimal1971 assemblagist1977 Neo-Geo1987 1922 D. H. Lawrence Aaron's Rod (N.Y. ed.) iii. 32 Into this reticence pieces of futurism, Omega cushions and Van-Gogh-like pictures exploded their colours. 1970 Oxf. Compan. Art 790/2 The Omega artists believed that the creative joy of the artist and craftsman should go into the making of articles for everyday use. 1973 Guardian 22 Jan. 8/1 The dining-room's Omega chairs attend its round painted table. 1986 New Yorker 18 Aug. 66/3 People said that the Omega furniture always fell to bits, but these chairs have stood up to the wear and tear of Bell family life pretty well. Compounds C1. Similative (in sense A. 2). omega-shaped adj. ΚΠ 1858 Househ. Words 4 Dec. 6/1 I look for the omega-shaped palm. 1991 Saudi Med. Jrnl. 12 62/2 The epiglottis is omega-shaped and floppy. C2. omega-form n. a shape resembling the Greek letter omega. ΚΠ 1880 Mrs. J. H. Gray Fourteen Months in Canton xxviii. 301 They are always in the Omega or horse-shoe form. 1959 M. Freeman Chinese Family & Marriage in Singapore vii. 206 Among all Chinese in Malaya..the omega-form is expressed [in tomb design] wherever possible by having an oval-brick border round the mound and projecting wings at the end. This entry has been updated (OED Third Edition, March 2004; most recently modified version published online March 2022). < n.adj.a1398
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