e·ra (îrə, ĕrə)
1. A period of time as reckoned from a specific date serving as the basis of its chronological system.
2. A period of time characterized by particular circumstances, events, or personages: the Colonial era of US history; the Reagan era.
3. The longest division of geologic time, made up of one or more periods.
[Late Latin aera, from Latin, counters, pl. of aes, aer-, bronze coin; see ayes- in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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