mid-14c., from Old French hiene, from Latin hyaena, from Greek hyaina "hyena," apparently a fem. formation from hys "pig," from PIE *su- "swine" (see sow (n.)). With fem. suffix -aina. So called for its bristles. Applied to cruel, treacherous, and greedy persons at least since 1670s. Adjectival forms that have been attempted in English include hyenaish, hyenaesque, hyenic, hyenine, hyenoid.

see hyena.

also aard-wolf, "small, insectivorous mammal native to East and Southern Africa, related to the hyena," 1833, from Afrikaans Dutch aardwolf, literally "earth-wolf," from aard "earth" (see earth (n.)) + wolf "wolf" (see wolf (n.)).

also cat-fish, name given to various types of fish, 1610s, originally probably in reference to the Atlantic wolf-fish, in reference to its ferocity, from cat (n.) + fish (n.).

The North American freshwater fish was so called by 1690s, probably for its "whiskers," or for the purring noise it is said to make when taken from the water. Greek had glanis, glaneos "catfish," in reference to the only European species (the Latin silurus, in English generally sheatfish), found north of the Alps, and the largest European fish other than the sturgeon. The name is based on glanos "hyena," the fish being "thus called because of its voracity and the sound it makes" [Beekes]. Compare dogfish. The ancients thought them sensitive to thunder and able to predict earthquakes and told of catching them of such size they had to be hauled ashore by oxen.