ep·​och | \ ˈe-pək How to pronounce epoch (audio) , ˈe-ˌpäk, US also and British usually ˈē-ˌpäk How to pronounce epoch (audio) \

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

Mingei International Museum, California Located along the Prado museum row in San Diego’s Balboa Park, the offbeat Mingei features historical and contemporary folk art, crafts, and designs from all epochs and every corner of the world. Joe Yogerst, National Geographic, "How to visit the best park museums in the U.S. and Canada," 13 Mar. 2019 His was an epoch of Empire and old Britain that is, definitively, no more. Juliet Rieden, Town & Country, "At 98, Prince Philip Is the Last of the Old-School Royals," 10 June 2019 When the lake’s fossils were forming, the world was in the Eocene epoch, a warm period in which South America, Antarctica, and Australia were still near each other, just before the final breakup of the ancient southern supercontinent Gondwana. Peter Wilf, National Geographic, "Prehistoric tree is first of its kind found below the Equator," 6 June 2019 Perhaps most importantly for the field as a whole, the findings reflect how ecology must mature in the Anthropocene epoch, as some scientists now describe the current period of human influence. Quanta Magazine, "Lizard Stowaways Revise Principle of Ecology," 24 Sep. 2014 The sense of epoch is enhanced by the use of period music—Debussy, Satie, Saint-Saëns—along with Thomas Adès’s original score. WSJ, "‘Colette’ Review: Literary History With a Modern Flavor," 20 Sep. 2018 And when the history of this awful American epoch is written, the tone-deaf abdication of fundamental ethics by social media platforms will be an overlay to the disaster. Matthew Gilbert, BostonGlobe.com, "David Simon versus Twitter," 24 June 2018 Glimpsing the early universe Much remains unknown about the epoch of reionization, such as what sources of light caused reionization. Charles Q. Choi, Scientific American, "Oldest Supermassive Black Hole Found from Universe’s Infancy," 6 Dec. 2017 Noguchi proposes that stars were formed in two different epochs under two different sets of circumstances. David Grossman, Popular Mechanics, "The Milky Way Died 7 Billion Years Ago And Came Back To Life," 24 Aug. 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

7 Jul 2019

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The first known use of epoch was in 1614

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English Language Learners Definition of epoch

: a period of time that is very important in history


ep·​och | \ ˈe-pək How to pronounce epoch (audio) \

Kids Definition of epoch

: a period that is important or memorable

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More from Merriam-Webster on epoch

Rhyming Dictionary: Words that rhyme with epoch

Thesaurus: All synonyms and antonyms for epoch

Spanish Central: Translation of epoch

Nglish: Translation of epoch for Spanish Speakers

Britannica English: Translation of epoch for Arabic Speakers

Britannica.com: Encyclopedia article about epoch

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to form ideas or theories about something

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