throw away vs discard

throw away is not a noun while discard is a noun.

Word	Noun	Adjective	Verb	Adverb
throw away	No	No	Yes	No
discard	Yes	No	Yes	No

As verbs, throw away and discard are synonyms defined as:

throw away (noun)	discard (noun)
	getting rid of something that is regarded as useless or undesirable
	(cards) the act of throwing out a useless card or of failing to follow suit
	anything that is cast aside or discarded

throw away (verb)	discard (verb)
to remove	throw or cast away
throw or cast away