• WordNet 3.6
    • n Pinnipedia seals; sea lions; walruses
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Webster's Revised Unabridged Dictionary
    • n. pl Pinnipedia (Zoöl) A suborder of aquatic carnivorous mammals including the seals and walruses; -- opposed to Fissipedia.
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Century Dictionary and Cyclopedia
    • pinnipedia In zoology, the pinnigrade, pinniped, or fin-footed aquatic carnivorous quadrupeds, constituting one of the prime divisions of the order Feræ or Carnivora, the other being the Fissipedia. In Iliiger's classification (1811) it was the thirteenth order of mammals. The body is prone, not raised from the ground: the limbs are modified into fins or flippers for swimming, and confined within the common integument beyond the elbows and knees; the feet are rotated backward. The first phalanges and digits of the manus and pes are enlarged beyond the others. The deciduous dentition is much reduced or rudimentary. The skull is greatly compressed between the orbits; the lacrymal bone is imperforate, intraorbital, and rarely confluent with the maxillary, which bounds the orbit; the palatines are not produced forward laterally; and there are extensive vacuities between the frontal and maxillary bones and between the tympanics and exoccipitals, There are three families — the Otariidæ or eared seals (sea-lions, sea-bears, etc.), the Phocidæ or seals proper, and the Trichechidæ or walruses. Also called Pinnipedes and Pinnigrada. See cuts under otary, seal, and walrus.
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Webster's Revised Unabridged Dictionary
NL. So called because their webbed feet are used as paddles or fins


In literature:

The two sub-orders into which this order is divided are: I, The Fissipedia, and II, The Pinnipedia.
"Natural History in Anecdote" by Various
The name is of course given to them to distinguish them from the corresponding division of the PINNIPEDIA.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard