reversioner vs party

reversioner and party both are nouns.

Word	Noun	Adjective	Verb	Adverb
reversioner	Yes	No	No	No
party	Yes	No	Yes	No

As nouns, party is a hypernym of reversioner; that is, party is a word with a broader meaning than reversioner:

reversioner (noun)	party (noun)
(law) a party who is entitled to an estate in reversion	an occasion on which people can assemble for social interaction and entertainment
	a gathering of people for pleasure
	an organization to gain political power
	a band of people associated temporarily in some activity
	a person involved in legal proceedings

reversioner (verb)	party (verb)
	have or participate in a party