defamation vs defame

defamation is a noun but defame is not a noun.

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

defamation (noun)	defame (noun)
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

defamation (verb)	defame (verb)
	charge falsely or with malicious intent; attack the good name and reputation of someone