Cathartes aura vs cathartid

Cathartes aura and cathartid both are nouns.

Word	Noun	Adjective	Verb	Adverb
Cathartes aura	Yes	No	No	No
cathartid	Yes	No	No	No

As nouns, cathartid is a hypernym of Cathartes aura; that is, cathartid is a word with a broader meaning than Cathartes aura:

Cathartes aura: a New World vulture that is common in South America and Central America and the southern United States
cathartid: large birds of prey superficially similar to Old World vultures

Other hypernyms of Cathartes aura include New World vulture.

Cathartes aura (noun)	cathartid (noun)
a New World vulture that is common in South America and Central America and the southern United States	large birds of prey superficially similar to Old World vultures