phrenologist vs mountebank

phrenologist and mountebank both are nouns.

Word	Noun	Adjective	Verb	Adverb
phrenologist	Yes	No	No	No
mountebank	Yes	No	No	No

As nouns, mountebank is a hypernym of phrenologist; that is, mountebank is a word with a broader meaning than phrenologist:

phrenologist: someone who claims to be able to read your character from the shape of your skull
mountebank: a flamboyant deceiver; one who attracts customers with tricks or jokes

Other hypernyms of phrenologist include charlatan.

phrenologist (noun)	mountebank (noun)
someone who claims to be able to read your character from the shape of your skull	a flamboyant deceiver; one who attracts customers with tricks or jokes