buckskin vs saddle horse

buckskin and saddle horse both are nouns.

Word	Noun	Adjective	Verb	Adverb
buckskin	Yes	No	No	No
saddle horse	Yes	No	No	No

As nouns, saddle horse is a hypernym of buckskin; that is, saddle horse is a word with a broader meaning than buckskin:

Other hypernyms of buckskin include mount, riding horse.

buckskin (noun)	saddle horse (noun)
horse of a light yellowish dun color with dark mane and tail	a lightweight horse kept for riding only
a soft yellowish suede leather originally from deerskin but now usually from sheepskin