What does "anniversary" mean?

Anniversary: The annual return of the day on which any notable event took place, or is wont to be celebrated; as, the anniversary of the Declaration of Independence.

Additional senses

  1. 2.(R. C. Ch.) The day on which Mass is said yearly for the soul of a deceased person; the commemoration of some sacred event, as the dedication of a church or the consecration of a pope.
  2. 3.The celebration which takes place on an anniversary day. Dryden.

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