overrating vs overestimate

overrating and overestimate both are nouns.

Word	Noun	Adjective	Verb	Adverb
overrating	Yes	No	No	No
overestimate	Yes	No	Yes	No

As nouns, overrating and overestimate are synonyms defined as:

overrating and overestimate: a calculation that results in an estimate that is too high

Other synonyms of overrating include overestimation, overreckoning.

overrating (noun)	overestimate (noun)
a calculation that results in an estimate that is too high	a calculation that results in an estimate that is too high
	an appraisal that is too high

overrating (verb)	overestimate (verb)
	make too high an estimate of
	assign too high a value to