Definition of epoch
1a : an event or a time marked by an event that begins a new period or developmentb : a memorable event or date
2a : an extended period of time usually characterized by a distinctive development or by a memorable series of eventsb : 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.
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
First Known Use: 1614
Synonym Discussion of epoch
EPOCH Defined for English Language Learners
Definition of epoch for English Language Learners
: a period of time that is very important in history
EPOCH Defined for Kids
Definition of epoch for Students
: a period that is important or memorable
Seen and Heard
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