jaguar n.

big spotted cat of the Americas (Felis onca), c. 1600, from Portuguese jaguar, from Tupi jaguara, said in old sources to denote any large beast of prey ["tygers and dogs," in Cullen's translation of Abbe Clavigero's "History of Mexico"]. Compare Tupi jacare "alligator." As a type of stylish British-made car from 1935; in this sense the abbreviation Jag is attested by 1951.