impinging vs hit

impinging and hit both are nouns.

Word	Noun	Adjective	Verb	Adverb
impinging	Yes	No	No	No
hit	Yes	No	Yes	No

As nouns, hit is a hyponym of impinging; that is, hit is a word with a more specific, narrower meaning than impinging:

Other hyponyms of impinging include collision, engagement, interlocking, mesh, meshing, flick, impact, touch, touching.

impinging (noun)	hit (noun)
the physical coming together of two or more things	the act of contacting one thing with another
	a conspicuous success
	(baseball) when a batter strikes a picthed ball into fair territory and arrives safely on base (without an error or a fielder's choice being made by the defense)
	a murder carried out by an underworld syndicate
	a connection made via the internet to another website
	a dose of a narcotic drug
	(physics) a brief event in which two or more bodies come together

impinging (verb)	hit (verb)
	pay unsolicited and usually unwanted sexual attention to
	make a strategic, offensive, assault against an enemy, opponent, or a target
	hit with a missile from a weapon
	hit the intended target or goal
	deal a blow to, either with the hand or with an instrument
	hit against; come into sudden contact with
	produce by manipulating keys or strings of musical instruments
	cause to move by striking
	affect or afflict suddenly, usually adversely
	reach a destination, either real or abstract
	drive something violently into a location
	reach a point in time, or a certain state or level
	cause to experience suddenly
	encounter by chance
	kill intentionally and with premeditation