noun
A measure of time
An end
A mark of punctuation
period is the general term for any portion of time; epoch and era are often used interchangeably to refer to a period marked by radical change, noteworthy developments, etc. an era, or epoch, of great discoveries, but epoch may specifically apply to the beginning of such a new period the steam engine marked an epoch in transportation, while era applies only to the entire period; age is applied to a period identified with some dominant personality or distinctive characteristic the Stone Age; eon refers to an indefinitely long period it all happened eons ago
See period in American Heritage Dictionary 4 Synonyms
See period in Webster's New World Roget's A-Z Thesaurus II
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