copycat vs doer

copycat and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
copycat	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of copycat; that is, doer is a word with a broader meaning than copycat:

Other hypernyms of copycat include actor, worker.

copycat (noun)	doer (noun)
someone who copies the words or behavior of another	a person who acts and gets things done