stack away vs bin

stack away is not a noun while bin is a noun.

Word	Noun	Adjective	Verb	Adverb
stack away	No	No	Yes	No
bin	Yes	No	Yes	No

As verbs, bin is a hyponym of stack away; that is, bin is a word with a more specific, narrower meaning than stack away:

Other hyponyms of stack away include computerise, computerize, victual, accumulate, amass, collect, compile, hoard, pile up, roll up, hive.

stack away (noun)	bin (noun)
	a container; usually has a lid
	the quantity contained in a bin

stack away (verb)	bin (verb)
keep or lay aside for future use	store in bins