ep·och | \ ˈe-pək , ˈe-ˌpäk , US also and British usually ˈē-ˌpäk \

Definition of epoch 

1a : an event or a time marked by an event that begins a new period or development

b : a memorable event or date

2a : an extended period of time usually characterized by a distinctive development or by a memorable series of events

b : a division of geologic time less than a period and greater than an age

3 : an instant of time or a date selected as a point of reference (as in astronomy)

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Synonyms for epoch


age, day, era, period, time

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Choose the Right Synonym for epoch

period, epoch, era, age mean a division of time. period may designate an extent of time of any length. periods of economic prosperity epoch applies to a period begun or set off by some significant or striking quality, change, or series of events. the steam engine marked a new epoch in industry era suggests a period of history marked by a new or distinct order of things. the era of global communications age is used frequently of a fairly definite period dominated by a prominent figure or feature. the age of Samuel Johnson

Did You Know?

Epoch comes to us, via Medieval Latin, from Greek epochē, meaning "cessation" or "fixed point." "Epochē," in turn, comes from the Greek verb epechein, meaning "to pause" or "to hold back." When "epoch" was first borrowed into English, it referred to the fixed point used to mark the beginning of a system of chronology. That sense is now obsolete, but today "epoch" is used in some fields (such as astronomy) with the meaning "an instant of time or a date selected as a point of reference." The "an event or a time that begins a new period or development" sense first appeared in print in the early 17th century, and "epoch" has been applied to defining moments or periods of time ever since.

Examples of epoch in a Sentence

The Civil War era was an epoch in 19th-century U.S. history. The development of the steam engine marked an important epoch in the history of industry.

Recent Examples on the Web

The brilliant architecture of this epoch and earlier periods earns Haifa UNESCO World Heritage status. Jeffrey Barken, Jewish Journal, "Haifa's on the rise with university leading the way," 11 July 2018 Scientists studied the Pliocene epoch, which happened a few million years ago. Avery Thompson, Popular Mechanics, "Antarctica's Ice May Be More Durable Than We Thought," 13 June 2018 Rather, the work preserves a sliver of the soundtrack of the era, music to fill elegant enclaves while epochs tectonically slid past each other. Matthew Guerrieri, BostonGlobe.com, "Mozart for an era of political machinations," 28 June 2018 And this giant isn’t some holdover from an ancient epoch. Brian Switek, Smithsonian, "Today’s Whales Are Huge, But Why Aren’t They Huger?," 27 June 2018 That is especially true in an epoch, like this one, of momentous choice and change. Lance Morrow, WSJ, "Did an Ancient Greek Anticipate Trump?," 22 June 2018 The researchers searched one-tenth of the entire sky visible from Earth and found just one quasar from this early epoch. Charles Q. Choi, Scientific American, "Oldest Supermassive Black Hole Found from Universe’s Infancy," 6 Dec. 2017 Temperatures were a little warmer then, so the epoch could be a good preview of a warmer Earth. Avery Thompson, Popular Mechanics, "Antarctica's Ice May Be More Durable Than We Thought," 13 June 2018 The layer where the head was found dates to the 9th century B.C., the epoch associated with the rival biblical kingdoms of Israel and Judah. Ilan Ben Zion, BostonGlobe.com, "Which mysterious biblical king is this? Scholars want to know," 9 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'epoch.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of epoch

1614, in the meaning defined at sense 1a

History and Etymology for epoch

Medieval Latin epocha, from Greek epochē cessation, fixed point, from epechein to pause, hold back, from epi- + echein to hold — more at scheme

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Last Updated

21 Jul 2018

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Time Traveler for epoch

The first known use of epoch was in 1614

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More Definitions for epoch



English Language Learners Definition of epoch

: a period of time that is very important in history


ep·och | \ ˈe-pək \

Kids Definition of epoch

: a period that is important or memorable

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