The Collaborative International Dictionary of English v.0.48:

Pinnatiped \Pin*nat"i*ped\, a. [L. pinnatus feathered + pes,
   pedis foot: cf. F. pinnatip[`e]de.] (Zool.)
   Having the toes bordered by membranes; fin-footed, as certain
   birds.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pinnatiped \Pin*nat"i*ped\, n. (Zool.)
   Any bird which has the toes bordered by membranes.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pinnatiped
    n 1: aquatic carnivorous mammal having a streamlined body
         specialized for swimming with limbs modified as flippers
         [syn: pinniped mammal, pinniped, pinnatiped]