imitate vs imitator

imitate is not a noun while imitator is a noun.

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

imitate (noun)	imitator (noun)
	someone who copies the words or behavior of another
	someone who (fraudulently) assumes the appearance of another

imitate (verb)	imitator (verb)
reproduce someone's behavior or looks
make a reproduction or copy of
appear like, as in behavior or appearance