ringer vs fraud

ringer and fraud both are nouns.

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

As nouns, fraud is a hypernym of ringer; that is, fraud is a word with a broader meaning than ringer:

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

ringer (noun)	fraud (noun)
(horseshoes) the successful throw of a horseshoe or quoit so as to encircle a stake or peg	intentional deception resulting in injury to another person
a contestant entered in a competition under false pretenses	something intended to deceive; deliberate trickery intended to gain an advantage
a person who is almost identical to another	the act of swindling by some fraudulent scheme
a person who rings church bells (as for summoning the congregation)	a person who makes deceitful pretenses