epoch

[ep-uh k or, esp. British, ee-pok] /ˈɛp ək or, esp. British, ˈi pɒk/
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).
5.
Astronomy.
  1. 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.
  2. 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) + -ē noun suffix
Related forms
subepoch, noun
superepoch, noun
Can be confused
epic, epoch.
Synonyms
1. age, date, era, time. See age.
Examples from the web for epoch
  • 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.
  • His guys lost three straight and their season was over and so was their epoch.
  • They really were the pioneers of the modern epoch.
  • It is in this weakness that we will probably find the secret of the contradictions of our epoch.
  • Its the start of a new epoch in human history.
  • The fiction stimulated fact in an epoch when scheduled public travel was speeding up under steam.
  • This epoch had life and intelligence in it.
British Dictionary definitions for epoch

epoch

/ˈiːpɒk/
noun
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
Derived Forms
epochal (ˈɛpˌɒkəl) adjective
epochally, adverb
Word Origin
C17: from New Latin epocha, from Greek epokhē cessation; related to ekhein to hold, have
Word Origin and History for epoch
n.

1610s, epocha, "point marking the start of a new period in time" (e.g. the founding of Rome, the birth of Christ, the Hegira), from Late Latin epocha, from Greek epokhe "stoppage, fixed point of time," from epekhein "to pause, take up a position," from epi "on" (see epi-) + ekhein "to hold" (see scheme (n.)). Transferred sense of "a period of time" is 1620s; geological usage (not a precise measurement) is from 1802.

epoch in Science
epoch
  (ěp'ək, ē'pŏk')   
The shortest division of geologic time. An epoch is a subdivision of a period.
epoch in Technology

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)