epoch

[ep-uhk or, esp. British, ee-pok]
noun
1.
a particular period of time marked by distinctive features, events, etc.: The treaty ushered in an epoch of peace and good will.
2.
the beginning of a distinctive period in the history of anything: The splitting of the atom marked an epoch in scientific discovery.
3.
a point of time distinguished by a particular event or state of affairs; a memorable date: His coming of age was an epoch in his life.
4.
Geology. any of several divisions of a geologic period during which a geologic series is formed. Compare age ( def 12 ). See table under geologic time.
5.
Astronomy.
a.
an arbitrarily fixed instant of time or date, usually the beginning of a century or half century, used as a reference in giving the elements of a planetary orbit or the like.
b.
the mean longitude of a planet as seen from the sun at such an instant or date.
6.
Physics. the displacement from zero at zero time of a body undergoing simple harmonic motion.

Origin:
1605–15; < Neo-Latin epocha < Greek epochḗ pause, check, fixed time, equivalent to ep- ep- + och- (variant stem of échein to have) + noun suffix

subepoch, noun
superepoch, noun

epic, epoch.


1. age, date, era, time. See age.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To epoch
Collins
World English Dictionary
epoch (ˈiːpɒk)
 
n
1.  a point in time beginning a new or distinctive period: the invention of nuclear weapons marked an epoch in the history of warfare
2.  a long period of time marked by some predominant or typical characteristic; era
3.  astronomy a precise date to which information, such as coordinates, relating to a celestial body is referred
4.  geology a unit of geological time within a period during which a series of rocks is formed: the Pleistocene epoch
5.  physics the displacement of an oscillating or vibrating body at zero time
 
[C17: from New Latin epocha, from Greek epokhē cessation; related to ekhein to hold, have]
 
epochal
 
adj
 
'epochally
 
adv

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Etymonline
Word Origin & History

epoch
1610s, "point marking the start of a new period in time" (e.g. the founding of Rome, the birth of Christ, the Hegira), from M.L. epocha, from Gk. epokhe "stoppage, fixed point of time," from epekhein "to pause, take up a position," from epi- "on" + ekhein "to hold." Transferred sense of "a period of
time" is 1620s; geological usage (not a precise measurement) is from 1802. Related: Epochal.
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
American Heritage
Science Dictionary
epoch   (ěp'ək, ē'pŏk')  Pronunciation Key 
The shortest division of geologic time. An epoch is a subdivision of a period.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
FOLDOC
Computing Dictionary

epoch definition


1. (Probably from astronomical timekeeping) A term used originally in Unix documentation for the time and date corresponding to zero in an operating system's clock and timestamp values.
Under most Unix versions the epoch is 1970-01-01 00:00:00 GMT; under VMS, it's 1858-11-17 00:00:00 (the base date of the US Naval Observatory's ephemerides); on a Macintosh, it's 1904-01-01 00:00:00.
System time is measured in seconds or ticks past the epoch. Weird problems may ensue when the clock wraps around (see wrap around), which is not necessarily a rare event; on systems counting 10 ticks per second, a signed 32-bit count of ticks is good only for 0.1 * 2**31-1 seconds, or 6.8 years. The one-tick-per-second clock of Unix is good only until 2038-01-18, assuming at least some software continues to consider it signed and that word lengths don't increase by then. See also wall time.
2. (Epoch) A version of GNU Emacs for the X Window System from NCSA.
[Jargon File]
(2004-06-10)
The Free On-line Dictionary of Computing, © Denis Howe 2010 http://foldoc.org
Cite This Source
Example sentences
It looks like they abandoned this place early on in the colonial epoch.
Broadly speaking, there have been two great epochs in our history, each with
  its own dominant national purpose.
The epoch dates from 1.8 million to 10000 years ago.
The first epoch extended from the middle of the 18th Century down through the
  19th.
Synonyms
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature