brown hyena vs hyaena

brown hyena and hyaena both are nouns.

Word	Noun	Adjective	Verb	Adverb
brown hyena	Yes	No	No	No
hyaena	Yes	No	No	No

As nouns, hyaena is a hypernym of brown hyena; that is, hyaena is a word with a broader meaning than brown hyena:

brown hyena: of southern Africa
hyaena: doglike nocturnal mammal of Africa and southern Asia that feeds chiefly on carrion

Other hypernyms of brown hyena include hyena.

brown hyena (noun)	hyaena (noun)
of southern Africa	doglike nocturnal mammal of Africa and southern Asia that feeds chiefly on carrion