For other uses, see Hyena (disambiguation). Hyenas or hyaenas (from Greek ὕαινα hýaina) are any feliform carnivoran mammals of the family Hyaenidae /haɪˈɛnᵻdiː/. With only four extant species, it is the fifth-smallest biological family in the Carnivora, and one of the smallest in the class Mammalia. Despite their low diversity, hyenas are unique and vital components of most African ecosystems.