hothead vs crank

hothead and crank both are nouns.

Word	Noun	Adjective	Verb	Adverb
hothead	Yes	No	No	No
crank	Yes	Yes	Yes	No

As nouns, crank is a hypernym of hothead; that is, crank is a word with a broader meaning than hothead:

Other hypernyms of hothead include churl, crosspatch, grouch, grump.

hothead (noun)	crank (noun)
a reckless impetuous irresponsible person	a hand tool consisting of a rotating shaft with parallel handle
a belligerent grouch	an amphetamine derivative (trade name Methedrine) used in the form of a crystalline hydrochloride; used as a stimulant to the nervous system and as an appetite suppressant
	a bad-tempered person
	a whimsically eccentric person

hothead (adjective)	crank (adjective)
	(used of boats) inclined to heel over easily under sail