pitchman vs crier

pitchman and crier both are nouns.

Word	Noun	Adjective	Verb	Adverb
pitchman	Yes	No	No	No
crier	Yes	No	No	No

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

pitchman: someone who travels about selling his wares (as on the streets or at carnivals)
crier: a peddler who shouts to advertise the goods he sells

Other hyponyms of pitchman include chapman, cheapjack, muffin man, sandboy, transmigrante.

pitchman (noun)	crier (noun)
someone who travels about selling his wares (as on the streets or at carnivals)	(formerly) an official who made public announcements
an aggressive salesman who uses a fast line of talk to sell something	a person who weeps
	a peddler who shouts to advertise the goods he sells