Forms: α. 7–9 epocha. β. epoche. γ. 7– epoch. [ad. late L. epocha, ad. Gr. ἐποχή stoppage, station, position (of a planet), fixed point of time, f. ἐπέχειν to arrest, stop, take up a position, f. ἐπί + ἔχειν to hold. Cf. Fr. époque, It. epoca.]
I. A fixed point in the reckoning of time.
1. Chron. The initial point assumed in a system of chronology; e.g., the date of the birth of Christ, of the Hegira, of the foundation of Rome, etc.; an ERA. Also, in wider sense, any date from which succeeding years are numbered. Now rare.
α. 1614. Selden, Titles Hon., 6. The residue wil fall neer the first yeer of the Chaldæan Epocha.
a. 1638. Mede, Wks., III. ix. 599. The Times of the Beast and the Woman’s being in the Wilderness have the same Epocha and beginning.
1726. trans. Gregory’s Astron., I. 252. The Epocha of the Olympiads, of all Profane ones, is the most Ancient.
β. a. 1658. Cleveland, Inund. of Trent, 138. Since we’re deliver’d let there be, From this Flood too another Epoche.
γ. 1658. Ussher, Ann., Ep. Rdr. (R.). In divers Ages and Nations, divers Epochs of time were used, and several forms of years.
1677. Hale, Prim. Orig. Man., II. iii. 148. The pretended Epoch of the Babylonians.
1758. Swinton, in Phil. Trans., L. 801. On the Greek brass coins of Sidon … both these epochs seem to have been used.
2. The beginning of a ‘new era’ or distinctive period in the history of mankind, a country, an individual, a science, etc. Phr., To make an epoch.
α. 1673. [R. Leigh], Transp. Reh., 55. Men that mark out Epocha’s are not born in many revolutions.
1756. Gentl. Mag., XXVI. 415. Botany … from hence boasts a new epocha.
1783. Blagden, in Phil. Trans., LXXIII. 360. The congelation of mercury, abstractedly considered, must be allowed to form a very curious and important epocha in the history of that metal.
1827. Sir J. Barrington, Own Times (1830), I. 18, note. A circumstance which the … Irish … considered as forming an epocha.
β. 1824. D’Israeli, Cur. Lit. (1859), II. 382. Every work which creates an epoch in literature is one of the great monuments of the human mind.
1841–4. Emerson, Ess. Spir. Laws, Wks. (Bohn), I. 68. The epochs of our life are not in the visible facts … but in a silent thought by the wayside.
1864. Burton, Scot Abr., I. v. 280. Luther’s Bible makes an epoch in the formation of the German language.
† b. The date of origin of a state of things, an institution, fashion, etc.; occasionally, an event marking such a date. Obs.
α. 1659. Pearson, Creed (1710), 198. Nor need we be ashamed that the Christian Religion which we profess, should have so known an Epocha, and so late an Original.
1788. Priestley, Lect. Hist., V. li. 390. Great fisheries have always been epocha’s of a great trade and navigation.
1789. Hist., in Ann. Reg., 14. The present crisis would become the epocha of a new splendor to the French monarchy.
1795. Wythe, Decis. Virginia, 41. Whether the time of the settlement were the epocha of the title will be enquired.
1824. E. Nares, Heraldic Anom. (ed. 2), II. 307. The year 1629 is reckoned the epocha of long perukes.
β. 1654. H. L’Estrange, Chas. I. (1655), 156. Now because the Warre was the Epoche, the Nativity day from whence all the series of this Kings troubles are to be computed.
γ. 1688. South, 36 Serm. (1720), I. 165 (J.). The Year Sixty, the grand Epoch of Falshood.
1761. Hume, Hist. Eng., I. xii. 290. This period … the epoch of the house of commons in England.
3. In wider sense: A fixed point of time.
a. The date, or assigned position in chronological sequence, of a historical event.
Now less precise than date, which indicates a particular year or smaller division of time.
β. 1661. Dryden, Astræa Redux, 108. Such, whose supine felicity but makes In story chasmes, in epoche’s [in some later edd. epocha’s, epocha] mistakes.
γ. 1697. Evelyn, Numism., v. 186. Epoches are sometimes noted in words at length.
1841. Elphinstone, Hist. Ind., I. 209. The date of his appearance;… the middle of the sixth century before Christ, an epoch which [etc.].
b. [= Fr. époque.] A precise date; the exact time at which an event takes place or is appointed to take place. Formerly gen.; now only with reference to natural phenomena (cf. 4 a).
α. 1761. State Papers, in Ann. Reg., 258/2. An offer to treat about these epochas.
γ. 1786. T. Jefferson, Wks. (1859), I. 570. To inform him … what other numbers [of arms] you expect to deliver, with the epochs of delivery.
1794. Burke, trans. Pref. Brissot’s Addr., Wks. 1815, VII. 312. To foresee them [the designs of the court] so well, as to mark the precise epoch on which they were to be executed.
1838. De Morgan, Ess. Probab. (Cabinet Cycl.), 123. When once the notion is obtained that a change of weather will follow that of the moon, the epoch is watched.
c. A point of time defined by the occurrence of particular events or the existence of a particular state of things; a ‘moment’ in the history of anything.
It is often uncertain whether a writer meant the word to be taken in this sense or in 5, since a given portion of time may be regarded either as a mere date or as a period.
α. 1728. Morgan, Algiers, I. iii. 73. Not long before this Epocha, so calamitous to that unhappy Country.
1777. G. Forster, Voy. round World, II. 103. In a warm climate … the epocha of maturity seems to happen at a much earlier age than in colder countries.
1791. Burke, Let. Member Nat. Assembly, Wks. VI. 9. I well remember, at every epocha of this wonderful history.
1801. Helen M. Williams, Sk. Fr. Rep., I. viii. 76. At the epocha of the [French] revolution.
1807. Southey, Espriella’s Lett. (1814), III. 74. The invention of the steam-engine, almost as great an epocha as the invention of printing.
1824. Hist. Gaming, 26. At one of those epochas the Earl married a Countess in her own right.
1830. Godwin, Cloudesley, I. xiii. 213. From this epocha there was a perpetual struggle in Cloudesley’s mind.
γ. 1823. J. Badcock, Dom. Amusem., Introd. 5. Davey and Brewster … sustain that character at the present epoch of Science.
1838. Carlyle, Chartism (1858), 3. At an epoch of history when the ‘National Petition’ carts itself in waggons along the streets.
1841–71. T. R. Jones, Anim. Kingd. (ed. 4), 510. At this epoch … the polyp presents two cavities distinct from each other.
1845. McCulloch, Taxation, II. v. (1852), 220. After the last-mentioned epoch … the production of beet-root sugar began rapidly to increase.
1875. Scrivener, Lect. Text N. Test., 7. Those noted up to the present epoch.
1882. Emma R. Pitman, Mission Life in Greece & Pal., 190. It was an epoch never to be forgotten in her life, when she commenced labouring in Joppa.
4. Astron. The point of time at which any phenomenon takes place; an arbitrarily fixed date (often the first day of a century or half-century) for which the elements necessary for computing the place of a heavenly body are tabulated. Also, the heliocentric longitude of a planet at such a date (more fully, the longitude of the epoch).
α. 1726. trans. Gregory’s Astron., I. 466. Their Mean Motions made between the said Epocha and the Time propos’d, being equated.
1789. Herschel, in Phil. Trans., LXXX. 20. I followed the shadow of the satellite with great attention up to the center, in order to secure a valuable epocha.
1795–8. T. Maurice, Hindostan (1820), I. I. iv. 128. By astronomers the word epocha is used to denote that particular point of the orbit of a planet, wherein that planet is, at some known moment of mean time, in a given meridian.
γ. 1790. Herschel, in Phil. Trans., LXXX. 488. Epochs of the mean longitude of the satellites.
1834. Nat. Philos. Astron., ix. 191/2 (Usef. Knowl. Soc.). The longitude of the sun, at some one time, which is called the epoch.
1858. Herschel, Outlines Astron., iv. (ed. 5), 168. They would be found … to differ by the exact difference of their local epochs.
II. A period of time. (Cf. similar use of era, term).
5. In early use, a chronological period dated from an ‘epoch’ in sense 1. In later use, a period of history defined by the prevalence of some particular state of things, by a connected series of events, or by the influence of some eminent person or group of persons.
α. 1628. Earle, Microcosm, Sordid Rich Man (Arb.), 99. His clothes were neuer young in our memory: you might make long Epocha’s from them.
1662. Stillingfl., Orig. Sacr., II. vii. § 8. 217. They make three Epocha’s, before the Law, under the Law, and the coming of the Messias.
c. 1720. Prior, Solomon on Van. World, III. 758. Scenes of war, and epochas of woe.
1794. R. J. Sulivan, View Nat., II. 201. Chronologers have divided the age of the world into six different epochas.
1824. L. Stanhope, Greece, 4. The most shining epocha of her history.
γ. c. 1800. K. White, Time, 385. Ages and epochs that destroy our pride.
1875. Stubbs, Const. Hist., II. xvi. 486. A period of eight years of peace between two epochs of terrible civil discord.
1883. Harper’s Mag., Feb., 467/2. ‘Ah, that indeed is a letter,’ sighs the lover of the Addisonian epoch.
b. A period in an individual’s life, or in the history of any continuous process.
α. 1768. Sterne, Sent. Journ. (1775), II. 132. There are three epochas in the empire of a Frenchwoman. She is coquette—then deist—then devote.
1771. Goldsm., Hist. Eng., III. 372. This is one of the most extraordinary epochas in English history.
1788. Holcroft, Life & Adv. Baron Trench, I. xiv. The second great and still more gloomy epocha of my life.
γ. 1853. Robertson, Serm., Ser. III. xx. 256. God’s treatment of the penitent divides itself in this parable into three distinct epochs.
1865. Draper, Intell. Devel. Europe, i. 9. We express our surprise when we witness actions unsuitable to the epoch of life.
c. Geol. A period or division of the history of the formation of the earth’s crust.
Chiefly used indiscriminately for any distinct portion of geological time. The International Congress of 1881 proposed to use the terms era, period, epoch, age to denote successively smaller divisions; but this has not been generally followed.
α. 1802. Playfair, Illustr. Hutton. Th., 123. The most ancient epocha of which any memorial exists in the records of the fossil kingdom.
γ. 1850. Lyell, 2nd Visit U.S., II. 247. The language of those who talk of ‘the epoch of existing continents.’
1871. Tyndall, Fragm. Sc. (ed. 6), I. viii. 268. But this would not produce a glacial epoch.
6. Physics. (See quots.)
1879. Thomson & Tait, Nat. Phil., I. I. § 54. The Epoch in a simple harmonic motion is the interval of time which elapses from the era of reckoning till the moving point first comes to its greatest elongation in the direction reckoned as positive, from its mean position or the middle of its range.
1882. Minchin, Unipl. Kinemat., 9. The maximum excursion it of the harmonic vibration x=a cos(2xt/T+α) is α…. The angle α is called the epoch angle, or simply the epoch.
7. Comb. [Perhaps after the equivalent compounds in German.] Epoch-forming adj.; epoch-making a., said chiefly of scientific discoveries or treatises.
1816. Coleridge, Lay Serm., 313. All the *epoch-forming revolutions of the Christian world.
1874. H. R. Reynolds, John Bapt., ii. 64. *Epoch-making men … of human history.
1881. W. Robertson Smith, Old Test. in Jewish Ch., iii. 56. This work of Ezra, and the covenant … were of epoch-making importance.
