impostor vs fraud

impostor and fraud both are nouns.

Word	Noun	Adjective	Verb	Adverb
impostor	Yes	No	No	No
fraud	Yes	No	No	No

As nouns, impostor and fraud are synonyms defined as:

Other synonyms of impostor include fake, faker, imposter, pretender, pseud, pseudo, role player, sham, shammer.

impostor (noun)	fraud (noun)
a person who makes deceitful pretenses	intentional deception resulting in injury to another person
	something intended to deceive; deliberate trickery intended to gain an advantage
	the act of swindling by some fraudulent scheme
	a person who makes deceitful pretenses