pile up vs fund

pile up is not a noun while fund is a noun.

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

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

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

pile up (noun)	fund (noun)
	a financial institution that sells shares to individuals and invests in securities issued by other companies
	a reserve of money set aside for some purpose
	a supply of something available for future use

pile up (verb)	fund (verb)
increase in amount by collecting or gathering	furnish money for
arrange into piles or stacks	place or store up in a fund for accumulation
get or gather together	convert (short-term floating debt) into long-term debt that bears fixed interest and is represented by bonds
	accumulate a fund for the discharge of a recurrent liability
	invest money in government securities
	provide a fund for the redemption of principal or payment of interest