crazy vs dotty

crazy is a noun but dotty is not a noun.

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

As adjectives, crazy and dotty are synonyms defined as:

Other synonyms of crazy include gaga, wild.

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

crazy (adjective)	dotty (adjective)
intensely enthusiastic about or preoccupied with	intensely enthusiastic about or preoccupied with
possessed by inordinate excitement	informal or slang terms for mentally irregular
foolish; totally unsound
affected with madness or insanity
bizarre or fantastic