maniac vs pyromaniac

maniac and pyromaniac both are nouns.

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

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

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

maniac (noun)	pyromaniac (noun)
an insane person	a person with a mania for setting things on fire
a person who has an obsession with or excessive enthusiasm for something

maniac (adjective)	pyromaniac (adjective)
wildly disordered