usable vs disposable

usable is not a noun while disposable is a noun.

Word	Noun	Adjective	Verb	Adverb
usable	No	Yes	No	No
disposable	Yes	Yes	No	No

usable (noun)	disposable (noun)
	an item that can be disposed of after it has been used

usable (adjective)	disposable (adjective)
convenient for use or disposal	designed to be disposed of after use
fit or ready for use or service	free or available for use or disposition
capable of being put to use