hap vs fortuity

hap and fortuity both are nouns.

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

As nouns, fortuity is a hypernym of hap; that is, fortuity is a word with a broader meaning than hap:

hap: an accidental happening
fortuity: anything that happens suddenly or by chance without an apparent cause

Other hypernyms of hap include accident, chance event, stroke.

hap (noun)	fortuity (noun)
an accidental happening	anything that happens suddenly or by chance without an apparent cause

hap (verb)	fortuity (verb)
come to pass