n. pl. an·ni·ver·sa·ries
1. The annually recurring date of a past event, as of personal or historical importance: a wedding anniversary; the anniversary of the founding of Rome.
2. A date that follows a certain event by a specified amount of time: his six-month anniversary of quitting smoking.
3. An event at which an anniversary is celebrated.
[Middle English anniversarie, from Medieval Latin (diēs) anniversāria, anniversary (day), from Latin, feminine of anniversārius, returning yearly : annus, year; see at- in the Appendix of Indo-European roots + versus, past participle of vertere, to turn; see wer-2 in the Appendix of Indo-European roots.]
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