wal·rus (wôl?r?s, w?l?-)n. pl. walrus or wal·rus·es A large marine mammal (Odobenus rosmarus) of Arctic regions, related to the seals and having two long tusks, tough wrinkled skin, and four flippers.[Dutch, of Scandinavian origin.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.walrus (?w??lr?s; ?w?l-) n, pl -ruses or -rus (Animals) a pinniped mammal, Odobenus rosmarus, of northern seas, having a tough thick skin, upper canine teeth enlarged as tusks, and coarse whiskers and feeding mainly on shellfish: family Odobenidae[C17: probably from Dutch, from Scandinavian; compare Old Norse hrosshvalr (literally: horse whale) and Old English horschwæl; see horse, whale]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014wal?rus (?w?l r?s, ?w?l-) n., pl. -rus?es, (esp. collectively) -rus. a large marine mammal, Odobenus rosmarus, of arctic seas, related to eared seals, having large tusks and a tough, wrinkled hide. [1645?55;