vassal vs feudatory

vassal and feudatory both are nouns.

Word	Noun	Adjective	Verb	Adverb
vassal	Yes	No	No	No
feudatory	Yes	Yes	No	No

As nouns, vassal and feudatory are synonyms defined as:

vassal and feudatory: a person holding a fief; a person who owes allegiance and service to a feudal lord

Other synonyms of vassal include liege, liege subject, liegeman.

vassal (noun)	feudatory (noun)
a person holding a fief; a person who owes allegiance and service to a feudal lord	a person holding a fief; a person who owes allegiance and service to a feudal lord

vassal (adjective)	feudatory (adjective)
	of or pertaining to the relation of a feudal vassal to his lord
	owing feudal allegiance to or being subject to a sovereign