recoil vs hap

recoil and hap both are nouns.

Word	Noun	Adjective	Verb	Adverb
recoil	Yes	No	Yes	No
hap	Yes	No	Yes	No

As verbs, hap is a hypernym of recoil; that is, hap is a word with a broader meaning than recoil:

Other hypernyms of recoil include come about, fall out, go on, happen, occur, pass, pass off, take place.

recoil (noun)	hap (noun)
a movement back from an impact	an accidental happening
the backward jerk of a gun when it is fired

recoil (verb)	hap (verb)
spring back, as from a forceful thrust	come to pass
draw back, as with fear or pain
spring back; spring away from an impact
come back to the originator of an action with an undesired effect