imitator vs worker

imitator and worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
imitator	Yes	No	No	No
worker	Yes	No	No	No

As nouns, worker is a hypernym of imitator; that is, worker is a word with a broader meaning than imitator:

Other hypernyms of imitator include actor, doer.

imitator (noun)	worker (noun)
someone who copies the words or behavior of another	sterile member of a colony of social insects that forages for food and cares for the larvae
someone who (fraudulently) assumes the appearance of another	a person who works at a specific occupation
	a member of the working class (not necessarily employed)
	a person who acts and gets things done