Anniversary
An anniversary is the date on which an event took place or an institution was founded in a previous year, and may also refer to the commemoration or celebration of that event. For example, the first event is the initial occurrence or, if planned, the inaugural of the event. One year later would be the first anniversary of that event. The word was first used for Catholic feasts to commemorate saints.
Most countries celebrate national anniversaries, typically called national days. These could be the date of independence of the nation or the adoption of a new constitution or form of government. The important dates in a sitting monarch’s reign may also be commemorated, an event often referred to as a “jubilee”.
Mensiversary (noun)
A day that marks an exact month (or specified number of months) since the occurrence of a significant event.
“monthiversary”
Anniversary (noun)
A day that is an exact number of years (to the day) since a given significant event occurred. Often preceded by an ordinal number indicating the number of years.
“Today is the fiftieth anniversary of the end of the war.”
Anniversary (noun)
A day subsequent in time to a given event by some significant period other than a year (especially as prefixed by the amount of time in question).
Anniversary (noun)
the date on which an event took place or an institution was founded in a previous year
“the 75th anniversary of the RAF”
“the 50th anniversary of the Battle of Britain”
Anniversary (noun)
the date on which a couple were married in a previous year
“he even forgot our tenth anniversary!”
Anniversary (noun)
the date on which a romance began in a previous month or week.