gaga vs crazy

gaga is not a noun while crazy is a noun.

Word	Noun	Adjective	Verb	Adverb
gaga	No	Yes	No	No
crazy	Yes	Yes	No	No

As adjectives, gaga and crazy are synonyms defined as:

Other synonyms of gaga include dotty, wild.

gaga (noun)	crazy (noun)
	someone deranged and possibly dangerous

gaga (adjective)	crazy (adjective)
intensely enthusiastic about or preoccupied with	intensely enthusiastic about or preoccupied with
mentally or physically infirm with age	possessed by inordinate excitement
	foolish; totally unsound
	affected with madness or insanity
	bizarre or fantastic