villein vs cotter

villein and cotter both are nouns.

Word	Noun	Adjective	Verb	Adverb
villein	Yes	No	No	No
cotter	Yes	No	No	No

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

villein: (Middle Ages) a person who is bound to the land and owned by the feudal lord
cotter: a medieval English villein

Other hyponyms of villein include cottier.

villein (noun)	cotter (noun)
(Middle Ages) a person who is bound to the land and owned by the feudal lord	fastener consisting of a wedge or pin inserted through a slot to hold two other pieces together
	a medieval English villein
	a peasant farmer in the Scottish Highlands