knickers vs buckskins

knickers and buckskins both are nouns.

Word	Noun	Adjective	Verb	Adverb
knickers	Yes	No	No	No
buckskins	Yes	No	No	No

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

Other hyponyms of knickers include britches, plus fours, trunk hose.

knickers (noun)	buckskins (noun)
(used in the plural) underpants worn by women	(used in the plural) breeches made of buckskin
(used in the plural) trousers ending above the knee