pile up vs run up

pile up and run up both are verbs.

Word	Noun	Adjective	Verb	Adverb
pile up	No	No	Yes	No
run up	No	No	Yes	No

As verbs, run up is a hyponym of pile up; that is, run up is a word with a more specific, narrower meaning than pile up:

Other hyponyms of pile up include corral, collect, pull in, come up, scrape, scrape up, scratch, chunk, lump, bale, catch, fund, fund.

pile up (verb)	run up (verb)
increase in amount by collecting or gathering	pile up (debts or scores)
arrange into piles or stacks	raise by using ropes and pulleys
get or gather together	fasten by sewing; do needlework
	make by sewing together quickly
	accumulate, sometimes as a debt