Noun: a long and distinct period of history with a particular feature or characteristic.
The Gothic style of architecture was popular during the feudal era.
This telephone is from another era, you don’t see them anymore today, except in museums.
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Merriam-Webster Online Dictionary
era (noun)1.
a) a fixed point in time from which a series of years is reckoned
b) a memorable or important date or event , especially one that begins a new period in the history of a person or thing
2.
a system of chronological notation computed from a given date as basis
3.
a) a period identified by some prominent figure or characteristic feature - the era of the horse and buggy
b) a stage in development (as of a person or thing)
c) a large division of geologic time usually shorter than an eon - Paleozoic era period
1.
earned run average
2.
Equal Rights Amendment