stack away vs collect

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

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

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

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

stack away (noun)	collect (noun)
	a short prayer generally preceding the lesson in the Church of Rome or the Church of England

stack away (adjective)	collect (adjective)
	payable by the recipient on delivery

stack away (verb)	collect (verb)
keep or lay aside for future use	assemble or get together
	get or bring together
	get or gather together
	call for and obtain payment of
	gather or collect

stack away (adverb)	collect (adverb)
	make a telephone call or mail a package so that the recipient pays