epoch

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

Definition of epoch

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

b :a memorable event or date

2 a :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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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 of epoch from the Web

The objects offer a glimpse of life during the American Revolution, and will be part of classroom lessons that help kids travel back to that epoch of history.

— deborah sullivan brennan, sandiegouniontribune.com, "History teachers travel back in time to Colonial Williamsburg," 30 Aug. 2017
Gas prices could rise 25 cents a gallon or more for several weeks in some parts of the country as the energy industry climbs out of hurricane Harvey's epoch rainfall in southeastern Texas.

— the washington post, OregonLive.com, "Harvey will likely push gas prices up, even as oil remains cheap," 29 Aug. 2017
The phrase represents an epoch in American thought.

— Longreads, "Late in Life, Thoreau Became a Serious Darwinist," 13 July 2017
Schneider responded with a hot clarinet, his more traditional musical vocabulary turning this performance into a kind of dialogue between distinct jazz epochs.

— howard reich, chicagotribune.com, "Review: Eric Schneider celebrates classic, hard-swinging jazz at Green Mill," 8 July 2017
For one, there were much warmer climates on Earth in the relatively recent past, such as during the Eocene epoch (between 56 million and 34 million years ago), and no signs of a runaway greenhouse effect, Zahnle said.

— tia ghose senior writer, Fox News, "Stephen Hawking: Earth could turn into hothouse planet like Venus," 7 July 2017
Portentous, considering that the current concentration of CO2, now more than 400 parts per million, is reaching a level not seen for perhaps three million years, since the Pliocene epoch.

— andrea gawrylewski, Scientific American, "Bug Lovers, Earth’s Many Apocalypses, the Surprising Minds of Vegetative Patients and Other New Science Books," 3 July 2017
Deep thinkers in ancient Greece and Rome recognized fossils as the remains of life-forms from earlier epochs.

— mike sager, Smithsonian, "Will the Public Ever Get to See the “Dueling Dinosaurs”?," 28 June 2017
Each of her books is a dense tapestry woven from encounters with those caught up in epoch-making events, from the second world war to the Chernobyl nuclear disaster of 1986.

— anna diamond, The Atlantic, "Russia’s Cyberwar Lab and Haiti’s Portable Pharmacies: The Week in Global-Affairs Writing," 23 June 2017

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.

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.

Origin and Etymology of 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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First Known Use: 1614

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