a large crocodilian, Alligator mississipiensis, of the southern US, having powerful jaws and sharp teeth and differing from the crocodiles in having a shorter and broader snout: family Alligatoridae (alligators and caymans)
2.
a similar but smaller species, A. sinensis, occurring in China near the Yangtse River
3.
any crocodilian belonging to the family Alligatoridae
4.
any of various tools or machines having adjustable toothed jaws, used for gripping, crushing, or compacting