names vs defamation

names and defamation both are nouns.

Word	Noun	Adjective	Verb	Adverb
names	Yes	No	No	No
defamation	Yes	No	No	No

As nouns, defamation is a hypernym of names; that is, defamation is a word with a broader meaning than names:

names: verbal abuse; a crude substitute for argument
defamation: a false accusation of an offense or a malicious misrepresentation of someone's words or actions

Other hypernyms of names include calumniation, calumny, hatchet job, obloquy, traducement.

names (noun)	defamation (noun)
verbal abuse; a crude substitute for argument	an abusive attack on a person's character or good name
	a false accusation of an offense or a malicious misrepresentation of someone's words or actions