blackmailer vs crook

blackmailer and crook both are nouns.

Word	Noun	Adjective	Verb	Adverb
blackmailer	Yes	No	No	No
crook	Yes	No	Yes	No

As nouns, crook is a hypernym of blackmailer; that is, crook is a word with a broader meaning than blackmailer:

blackmailer: a criminal who extorts money from someone by threatening to expose embarrassing information about them
crook: someone who has committed a crime or has been legally convicted of a crime

Other hypernyms of blackmailer include criminal, felon, malefactor, outlaw.

blackmailer (noun)	crook (noun)
a criminal who extorts money from someone by threatening to expose embarrassing information about them	a long staff with one end being hook shaped
	someone who has committed a crime or has been legally convicted of a crime
	a circular segment of a curve

blackmailer (verb)	crook (verb)
	bend or cause to bend