wacko vs flake

wacko and flake both are nouns.

Word	Noun	Adjective	Verb	Adverb
wacko	Yes	No	No	No
flake	Yes	No	Yes	No

As nouns, flake is a hypernym of wacko; that is, flake is a word with a broader meaning than wacko:

Other hypernyms of wacko include eccentric, eccentric person, geek, oddball.

wacko (noun)	flake (noun)
a person who is regarded as eccentric or mad	a small fragment of something broken off from the whole
	a person with an unusual or odd personality
	a crystal of snow

wacko (verb)	flake (verb)
	come off in flakes or thin small pieces
	cover with flakes or as if with flakes
	form into flakes