Orca (n.)

"killer whale," introduced as a generic term for the species by 1841, from earlier use in scientific names, from Latin orca "cetacean, a kind of whale." Earlier in English, orc, ork "large marine mammal, deadly sea-creature" (by mid-17c.), from French orque, had been used vaguely of sea monsters (see orc). Strong, ferocious, and predatory, they are the only cetaceans which habitually prey upon warm-blooded animals.