cottar vs fastening

cottar and fastening both are nouns.

Word	Noun	Adjective	Verb	Adverb
cottar	Yes	No	No	No
fastening	Yes	No	No	No

As nouns, fastening is a hypernym of cottar; that is, fastening is a word with a broader meaning than cottar:

cottar: fastener consisting of a wedge or pin inserted through a slot to hold two other pieces together
fastening: restraint that attaches to something or holds something in place

Other hypernyms of cottar include fastener, fixing, holdfast.

cottar (noun)	fastening (noun)
fastener consisting of a wedge or pin inserted through a slot to hold two other pieces together	the act of fastening things together
a peasant farmer in the Scottish Highlands	restraint that attaches to something or holds something in place