pinniped - aquatic carnivorous mammal having a streamlined body specialized for swimming with limbs modified as flippersaquatic mammal - whales and dolphins; manatees and dugongs; walruses; seals seal - any of numerous marine mammals that come on shore to breed; chiefly of cold regions sea horse, seahorse, walrus - either of two large northern marine mammals having ivory tusks and tough hide over thick blubber pod - a group of aquatic mammals |