Synonyms:
fanatic, fanatical, overzealous, rabid
Meaning: marked by excessive enthusiasm for and intense devotion to a cause or idea; "rabid isolationist"
noun
meaning of the word
Synonyms:
fanatic, fiend
Meaning: 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
Usage examples
"Bell was always a fanatic in praise of poverty," said Mrs. Dale.
A true fanatic, his promptings were reasons enough for his actions.
That forehead marked the dreamer, the idealist, the introvert, just as the eyes and the thin, straight nose betrayed the fanatic.
"'I don't call myself a religious man,' says I, 'or a fanatic in moral bigotry, but I can't stand still and see a man who has built up his business by his own efforts and brains and risk be robbed by an unscrupulous trickster who is a menace to the public good.'