croc·o·dile 
(krŏkə-dīl′)
(krŏkə-dīl′)n.
1. Any of various large aquatic reptiles of the family Crocodylidae that are native to tropical and subtropical regions and have thick, armorlike skin and long tapering jaws.
2. A crocodilian reptile, such as an alligator, caiman, or gharial.
3. Leather made from crocodile skin.
4. Chiefly British A line of people, especially pupils or choir members, standing two abreast.
[Middle English cocodril, from Old French, from Latin cocodrillus, variant of crocodīlus, from Greek krokodīlos : krokē, pebble + drīlos, circumcised man, worm.]