blackmailer vs malefactor

blackmailer and malefactor both are nouns.

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

As nouns, malefactor is a hypernym of blackmailer; that is, malefactor 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
malefactor: someone who has committed a crime or has been legally convicted of a crime

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

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