heap up vs collect

heap up is not a noun while collect is a noun.

Word	Noun	Adjective	Verb	Adverb
heap up	No	No	Yes	No
collect	Yes	Yes	Yes	Yes

As verbs, collect is a hypernym of heap up; that is, collect is a word with a broader meaning than heap up:

Other hypernyms of heap up include garner, gather, pull together.

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

heap up (adjective)	collect (adjective)
	payable by the recipient on delivery

heap up (verb)	collect (verb)
arrange into piles or stacks	assemble or get together
	get or bring together
	get or gather together
	call for and obtain payment of
	gather or collect

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