Epoch

/ˈiːpɒk/ · noun

Meaning

A particular period of history, or of a person's life, especially one considered noteworthy or remarkable..

Definitions by Sense

1. A particular period of history, or of a person's life, especially one considered noteworthy or remarkable.
2. A notable event which marks the beginning of such a period.
3. (chronology, astronomy, computing) A specific instant in time, chosen as the point of reference or zero value of a system that involves identifying instants of time.
4. (geology) A geochronologic unit of hundreds of thousands to millions of years; a subdivision of a period, and subdivided into ages (or sometimes subepochs).
5. (machine learning) One complete presentation of the training data set to an iterative machine learning algorithm.
6. (sciences, transitive) To divide (data) into segments by time period.

Example Sentences

I grew bitter in my words—I believed the worst of everyone; nay, I sometimes doubted the affection of my kind, my indulgent parents. But let me hastily pass over this vain and profitless epoch,—the fierce tempest, and the weary calm, were but the appointed means by which I reached the harbour of faith and rest.

And it occasionally happens that a period in which one had, hitherto, been mainly looking for the coming to birth of new things, suddenly reveals itself as an epoch of fading and decay.

UNIX epoch; J2000 epoch

Appendix A gives formulae for the calculation of the orbital elements of the planets at any time referred to the mean ecliptic and equinox of the epoch of noon on 1st January 2000; this is called the J2000 epoch.

There are two major epoch times associated with most timestamps: 1970-01-01 00:00:00 and 1601-01-01 00:00:00. The first, starting in 1970, is traditionally referred to as POSIX time as it is a common timestamp in UNIX and UNIX-like systems.

The .NET epoch is midnight at the start of January 1st, AD 1, although that's AD 1 in a proleptic Gregorian calendar, which refers to even more complexity we haven't talked about yet.

Now during the time of the glacial epoch the greatest distance of the sun in winter was 98¼ millions of miles, whereas it is now, in winter, only 91½ millions of miles, the mean distance being taken as 93 million miles.

Phoenix and Lubbock are both caught in severe drought, and it is going to get much worse. We may see many such [dust] storms in the decades ahead, along with species extinctions, radical disturbance of ecosystems, and intensified social conflict over land and water. Welcome to the Anthropocene, the epoch when humans have become a major geological and climatic force.

Synonyms for epoch

Antonyms for epoch

Related Words

Word Forms

• epochs
• epocha
• epoching
• epoched

Usage Notes

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