[syn: epoch, date of reference]
3. a unit of geological time that is a subdivision of a period and is itself divided into ages;
The Collaborative International Dictionary of English v.0.48:
Epoch \Ep"och\ ([e^]p"[o^]k or [=e]"p[o^]k; 277), n. [LL.
epocha, Gr. 'epochh` check, stop, an epoch of a star, an
historical epoch, fr. 'epe`chein to hold on, check; 'epi`
upon + 'e`chein to have, hold; akin to Skr. sah to overpower,
Goth. sigis victory, AS. sigor, sige, G. sieg: cf. F.
['e]poque. See Scheme.]
1. A fixed point of time, established in history by the
occurrence of some grand or remarkable event; a point of
time marked by an event of great subsequent influence; as,
the epoch of the creation; the birth of Christ was the
epoch which gave rise to the Christian era.
In divers ages, . . . divers epochs of time were
Great epochs and crises in the kingdom of God.
The acquittal of the bishops was not the only event
which makes the 30th of June, 1688, a great epoch in
Note: Epochs mark the beginning of new historical periods,
and dates are often numbered from them.
2. A period of time, longer or shorter, remarkable for events
of great subsequent influence; a memorable period; as, the
epoch of maritime discovery, or of the Reformation. "So
vast an epoch of time." --F. Harrison.
The influence of Chaucer continued to live even
during the dreary interval which separates from one
another two important epochs of our literary
history. --A. W. Ward.
3. (Geol.) A division of time characterized by the prevalence
of similar conditions of the earth; commonly a minor
division or part of a period.
The long geological epoch which stored up the vast
coal measures. --J. C.
(a) The date at which a planet or comet has a longitude or
(b) An arbitrary fixed date, for which the elements used
in computing the place of a planet, or other heavenly
body, at any other date, are given; as, the epoch of
Mars; lunar elements for the epoch March 1st, 1860.
Syn: Era; time; date; period; age.
Usage: Epoch, Era. We speak of the era of the
Reformation, when we think of it as a period, during
which a new order of things prevailed; so also, the
era of good feeling, etc. Had we been thinking of the
time as marked by certain great events, or as a period
in which great results were effected, we should have
called the times when these events happened epochs,
and the whole period an epoch.
The capture of Constantinople is an epoch in the
history of Mahometanism; but the flight of
Mahomet is its era. --C. J. Smith.
Moby Thesaurus II by Grady Ward, 1.0:
20 Moby Thesaurus words for "epoch":
Bronze Age, Dark Ages, Depression Era, Golden Age, Ice Age,
Iron Age, Jacksonian Age, Middle Ages, New Deal Era,
Prohibition Era, Silver Age, Steel Age, Stone Age, age, days, era,
glacial epoch, interval, term, time