I. noun 1. a large semiaquatic reptile similar to a crocodile but with a broader and shorter head, native to the Americas and China.●Genus Alligator, family Alligatoridae, order Crocodylia: the American alligator ( A. mississippiensis) and the Chinese alligator ( A. sinensis). 2. [ mass noun] — the skin of the alligator or material resembling it.
– origin late 16th cent.: from Spanish el lagarto ‘the lizard’, probably based on Latin lacerta.