goofy vs whacky

goofy and whacky both are adjectives.

Word	Noun	Adjective	Verb	Adverb
goofy	No	Yes	No	No
whacky	No	Yes	No	No

As adjectives, goofy and whacky are synonyms defined as:

Other synonyms of goofy include silly, wacky, zany.

goofy (adjective)	whacky (adjective)
ludicrous, foolish	ludicrous, foolish
	informal or slang terms for mentally irregular