overzealous vs fanatical

overzealous and fanatical both are adjectives.

Word	Noun	Adjective	Verb	Adverb
overzealous	No	Yes	No	No
fanatical	No	Yes	No	No

As adjectives, overzealous and fanatical are synonyms defined as:

overzealous and fanatical: marked by excessive enthusiasm for and intense devotion to a cause or idea

Other synonyms of overzealous include fanatic, rabid.

overzealous (adjective)	fanatical (adjective)
marked by excessive enthusiasm for and intense devotion to a cause or idea	marked by excessive enthusiasm for and intense devotion to a cause or idea