lobbyist vs lobby

lobbyist and lobby both are nouns.

Word	Noun	Adjective	Verb	Adverb
lobbyist	Yes	No	No	No
lobby	Yes	No	Yes	No

lobbyist (noun)	lobby (noun)
someone who is employed to persuade legislators to vote for legislation that favors the lobbyist's employer	a large entrance or reception room or area
	an interest group that tries to influence legislators or bureaucrats to act in their favor, typically through lobbying
	the people who support some common cause or business or principle or sectional interest

lobbyist (verb)	lobby (verb)
	detain in conversation by or as if by holding on to the outer garments of; as for political or economic favors