
[Medieval Latin epocha, measure of time, from Greek epokhē, a point in time.]
This was an epoch-making moment in the history of Egypt, like the day a dam bursts—N. Barber, 1984
There were a large number of epoch-making events whose 40th anniversaries were celebrated towards the end of last year, as readers will undoubtedly recall—Times Educational Supplement, 2004.
| epitome, epithet, epistle | |
| eponym, eponymous, equable, equitable, equal |
For more information on epoch, visit Britannica.com.
[Etymology: Gk: ‘pause’] time A specific point in time or the interval between two such points, but not as such a measure of time. In astronomy it is usually the single point, otherwise it generally has the extended meaning; in geology it can be millions of years. By contrast, an epoch within the initial cosmic ‘big bang’ is less than a microsecond.
geology The fourth-largest unit (following period) of the geochronologic scale, and the tertiary one into which it, excluding the pre-Cambrian, is divided: examples include Pliocene, Pleistocene, and Holocene. Typical size is about 15 million years.
The starting date from which time is measured as a number of days or minutes or seconds, etc. In computer applications, epochs are used to maintain a time reference as a single number for ease of computation. Otherwise, depending on the granularity of time desired, every point in time would have to be stored with some of or all of the components of the time hierarchy, including year, month, day, hour, minute, second, millisecond, microsecond and nanosecond. Following are the various epochs in use. See also EPOC.
System Epoch Measured in Unix Jan. 1, 1970 Seconds Java Jan. 1, 1970 Milliseconds Windows files Jan. 1, 1601 Ticks (100 ns) Windows dates Jan. 1, 0001 Ticks (100 ns) Mac Jan. 1, 2001 Seconds Earlier Mac Jan. 1, 1904 Seconds Excel Dec. 31, 1899 Days DB2 Dec. 31, 1899 Days Unununium Jan. 1, 2000 Microseconds
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[Unix: prob.: from astronomical timekeeping] The time and date corresponding to 0 in an operating system's clock and timestamp values. Under most Unix versions the epoch is 00:00:00 GMT, January 1, 1970; under VMS, it's 00:00:00 of November 17, 1858 (base date of the U.S. Naval Observatory's ephemerides); on a Macintosh, it's the midnight beginning January 1 1904. 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 6.8 years. The 1-tick-per-second clock of Unix is good only until January 18, 2038, assuming at least some software continues to consider it signed and that word lengths don't increase by then. See also wall time. Microsoft Windows, on the other hand, has an epoch problem every 49.7 days — but this is seldom noticed as Windows is almost incapable of staying up continuously for that long.
We do not choose our historical epoch, or the country of our birth, or the immediate circumstances of our upbringing.
— Joseph Epstein.
Tutor's tip: The "epic" (a long poem or other writing telling of a nation's heroic acts) adventure tale takes place during the "epoch" (a period of time in history or in geology) after the Bronze Age.
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| Look up epoch in Wiktionary, the free dictionary. |
An epoch, Epoch or EPOCH may refer to:
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Dansk (Danish)
n. - epoke, periode, tid
Nederlands (Dutch)
tijdvak, periode, belangrijke datum of gebeurtenis, mijlpaal
Français (French)
n. - époque, période, (fig) date
Ελληνική (Greek)
n. - εποχή, χρονική περίοδος
Português (Portuguese)
n. - época (f), período (m)
Русский (Russian)
эпоха, эра, век
Español (Spanish)
n. - época, era, período
中文(简体)(Chinese (Simplified))
新纪元, 时期, 时代
中文(繁體)(Chinese (Traditional))
n. - 新紀元, 時期, 時代
한국어 (Korean)
n. - 신기원, 지층 구성 기간
日本語 (Japanese)
n. - 新紀元, 画期的なでき事, 時代, 世
العربيه (Arabic)
(الاسم) دور, عهد
עברית (Hebrew)
n. - עידן, מאורע חשוב
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