1. A period of time as reckoned from a specific date serving as the basis of its chronological system. 2a. A period of time characterized by particular circumstances, events, or personages: the Colonial era of U.S. history; the Reagan era.b. A point that marks the beginning of such a period of time. See synonyms at period. 3. The longest division of geologic time, made up of one or more periods.
ETYMOLOGY:
Late Latin aera, from Latin, counters, pl. of aes, aer-, bronze coin. See ayes- in Appendix I.
îr
, 
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