mare vs Equus caballus

mare and Equus caballus both are nouns.

Word	Noun	Adjective	Verb	Adverb
mare	Yes	No	No	No
Equus caballus	Yes	No	No	No

As nouns, Equus caballus is a hypernym of mare; that is, Equus caballus is a word with a broader meaning than mare:

mare: female equine animal
Equus caballus: solid-hoofed herbivorous quadruped domesticated since prehistoric times

Other hypernyms of mare include horse.

mare (noun)	Equus caballus (noun)
female equine animal	solid-hoofed herbivorous quadruped domesticated since prehistoric times
a dark region of considerable extent on the surface of the moon