maniac vs weirdo

maniac and weirdo both are nouns.

Word	Noun	Adjective	Verb	Adverb
maniac	Yes	Yes	No	No
weirdo	Yes	No	No	No

As nouns, weirdo is a hyponym of maniac; that is, weirdo is a word with a more specific, narrower meaning than maniac:

Other hyponyms of maniac include crazy, looney, loony, nutcase, bedlamite, pyromaniac, madwoman, madman.

maniac (noun)	weirdo (noun)
an insane person	someone unpleasantly strange or eccentric
a person who has an obsession with or excessive enthusiasm for something	someone deranged and possibly dangerous

maniac (adjective)	weirdo (adjective)
wildly disordered