Hyaena hyaena vs hyaena

Hyaena hyaena and hyaena both are nouns.

Word	Noun	Adjective	Verb	Adverb
Hyaena hyaena	Yes	No	No	No
hyaena	Yes	No	No	No

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

Hyaena hyaena: of northern Africa and Arabia and India
hyaena: doglike nocturnal mammal of Africa and southern Asia that feeds chiefly on carrion

Other hypernyms of Hyaena hyaena include hyena.

Hyaena hyaena (noun)	hyaena (noun)
of northern Africa and Arabia and India	doglike nocturnal mammal of Africa and southern Asia that feeds chiefly on carrion