whacky vs goofy

whacky and goofy both are adjectives.

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

As adjectives, whacky and goofy are synonyms defined as:

Other synonyms of whacky include silly, wacky, zany.

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