# epoch

> English word · Noun · IPA /ˈiːpɒk/ · frequency rank #22,662

## Definitions
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. A specific instant in time, chosen as the point of reference or zero value of a system that involves identifying instants of time.
4. A geochronologic unit of hundreds of thousands to millions of years; a subdivision of a period, and subdivided into ages (or sometimes subepochs).
5. One complete presentation of the training data set to an iterative machine learning algorithm.

## Etymology
From Medieval Latin epocha, from Ancient Greek ἐποχή (epokhḗ, “a check, cessation, stop, pause, epoch of a star, i.e., the point at which it seems to halt after reaching the highest, and generally the place of a star; hence, a historical epoch”), from ἐπέχω (epékhō, “I hold in, check”), from ἐπι- (epi-, “upon”) + ἔχω (ékhō, “I have, hold”). Doublet of epoche.

## Easily confused with
- **etch** (https://plainspell.com/en/vs/epoch-vs-etch)
- **epoxy** (https://plainspell.com/en/vs/epoch-vs-epoxy)
- **Erich** (https://plainspell.com/en/vs/epoch-vs-erich)
- **Eph** (https://plainspell.com/en/vs/eph-vs-epoch)
- **Epo** (https://plainspell.com/en/vs/epo-vs-epoch)
- **each** (https://plainspell.com/en/vs/each-vs-epoch)
- **EPIC** (https://plainspell.com/en/vs/epic-vs-epoch)
- **EEOC** (https://plainspell.com/en/vs/eeoc-vs-epoch)
- **Enoch** (https://plainspell.com/en/vs/enoch-vs-epoch)
- **epics** (https://plainspell.com/en/vs/epics-vs-epoch)

## Common misspellings (7)
`eopch`, `epcoh`, `epocch`, `epochh`, `epohc`, `eppoch`, `peoch`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/epoch