fanatic

  • (s) marked by excessive enthusiasm for and intense devotion to a cause or idea
    • rabid isolationist
    fanatical, overzealous, rabid,

Nouns

  • (n) a person motivated by irrational enthusiasm (as for a cause)
    • A fanatic is one who can't change his mind and won't change the subject --Winston Churchill
    fiend,

Synonyms

fiend fanatical overzealous rabid

Words of close approximity

fanatical fanatically fanaticism