Hyena
Middle English: via Latin from Greek huaina, feminine of hus ‘pig’ (the transference of the term probably being because the animal's mane was thought to resemble a hog's bristles).
wiktionary
From Middle English hiena, variant of hyene, from Old French hiene, from Medieval Latin hyēna, from Latin hyaena, from Ancient Greek ὕαινα(húaina). Displaced native Old English nihtgenġe (literally "night walker").
etymonline
hyena (n.)
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.