A centennial is defined as a 100th anniversary, or a celebration of a 100th anniversary.(noun)
A 100th anniversary of a city is an example of a centennial.
The definition of centennial is something related to a 100th anniversary.(adjective)
A party to celebrate a 100th anniversary of an event is an example of a centennial.
See centennial in Webster's New World College Dictionary
Origin: < L centum, hundred + annus, year (see annual) + -al
See centennial in American Heritage Dictionary 4
Origin: Latin centum, hundred; see dekm̥ in Indo-European roots
Origin: + (bi)ennial.
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