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)

Keep scrolling for more

Synonyms for epoch


age, day, era, period, time

Visit the Thesaurus for More 

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

On every continent mammals on average were a lot larger in the late Pleistocene, the geologic epoch spanning from around 2.5 million until about 11,700 years ago. Jason G. Goldman, Scientific American, "In 200 Years Cows May Be the Biggest Land Mammals on the Planet," 20 Apr. 2018 But from a labor force perspective, 1980 was a different epoch. Anthony P. Carnevale, Washington Post, "The Education and Labor departments were made for each other," 22 June 2018 His vision in Florida was inspired by gardens in Japan; each of Morikami’s six gardens reflects a style from a different epoch, beginning with the 9th century. New York Times, "6 Great Gardens to Visit in Florida," 16 Feb. 2018 The mini-series—either a celebration of a Catholic, conservative epoch or a tale of female empowerment, depending on the viewer’s bias—drew big ratings throughout central Europe. The Economist, "Habsburg culture is back in vogue," 21 June 2018 Specifically, the researchers were interested in what happened to the ice sheet during the Pliocene epoch, the geologic period from about 5.4 million years ago to around 2.5 million. Avery Thompson, Popular Mechanics, "Antarctica's Ice May Be More Durable Than We Thought," 13 June 2018 One theory posits that marine waters inundated western Amazonia during the Miocene epoch, 23 million to five million years ago, possibly creating an environment where hosts of new species could evolve. Angela Posada-swafford, Scientific American, "Amazon Rain Forest May Have Once Been a Giant Marine Lake," 1 July 2017 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

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.

See More

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

Keep scrolling for more

Learn More about epoch

Listen to Our Podcast about epoch

Dictionary Entries near epoch








Statistics for epoch

Last Updated

27 Oct 2018

Look-up Popularity

Time Traveler for epoch

The first known use of epoch was in 1614

See more words from the same year

Keep scrolling for more

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

Keep scrolling for more

Comments on epoch

What made you want to look up epoch? Please tell us where you read or heard it (including the quote, if possible).


to clear from alleged fault or guilt

Get Word of the Day daily email!

Test Your Vocabulary

Difficult Vocab Quiz

  • the-education-of-achilles-eugne-delacroix
  • Which is a synonym of discomfit?
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!