The definition of an era is a period of time in history that is unified by cultural or historical factors.(noun)
An example of an era is the industrial era.
See era in Webster's New World College Dictionary
Origin: LL aera, era, earlier senses, “counters,” “items of account” < pl. of L aes (gen. aeris), copper: see ore
See era in American Heritage Dictionary 4
Origin: Late Latin aera
Origin: , from Latin, counters
Origin: , pl. of aes, aer-, bronze coin; see ayes- in Indo-European roots.
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