The definition of a fanatic is a person who is overly excited and interested in something.
(noun)An example of fanatic is someone with a room devoted to Elvis Presley in their two-bedroom house.
See fanatic in Webster's New World College Dictionary
adjective
Origin: < L fanaticus, of a temple, hence enthusiastic, inspired < fanum, a temple: see fane
noun
See fanatic in American Heritage Dictionary 4
noun
Origin:
Origin: Latin fānāticus, inspired by orgiastic rites, pertaining to a temple
Origin: , from fānum, temple; see dhēs- in Indo-European roots
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