n. pl. hip·po·pot·a·mus·es or hip·po·pot·a·mi (-mī′)
1. A large, chiefly aquatic African herbivorous mammal (Hippopotamus amphibius) having thick, dark, almost hairless skin, short legs with four toes, and a broad, wide-mouthed muzzle. Also called river horse.
2. The pygmy hippopotamus.
[Latin, from Greek hippopotamos : hippos, horse; see ekwo- in the Appendix of Indo-European roots + potamos, river; see pet- in the Appendix of Indo-European roots.]
(click for a larger image)hippopotamus
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