adman vs huckster

adman and huckster both are nouns.

Word	Noun	Adjective	Verb	Adverb
adman	Yes	No	No	No
huckster	Yes	No	Yes	No

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

Other hyponyms of adman include booster, plugger, promoter, tout, touter.

adman (noun)	huckster (noun)
someone whose business is advertising	a seller of shoddy goods
	a person who writes radio or tv advertisements

adman (verb)	huckster (verb)
	sell or offer for sale from place to place
	wrangle (over a price, terms of an agreement, etc.)