racketeer vs underworld

racketeer and underworld both are nouns.

Word	Noun	Adjective	Verb	Adverb
racketeer	Yes	No	Yes	No
underworld	Yes	No	No	No

racketeer (noun)	underworld (noun)
someone who commits crimes for profit (especially one who obtains money by fraud or extortion)	(religion) the world of the dead
	the criminal class

racketeer (verb)	underworld (verb)
carry on illegal business activities involving crime