pinniped vs sea lion

pinniped

noun
  • Any of various large marine mammals belonging to the superfamily (formerly considered a suborder) Pinnipedia comprising walruses, eared seals and earless seals. 

adj
  • Pertaining to or similar to such a mammal. 

sea lion

noun
  • A marine mammal of any of several genera in the family Otariidae (the eared seals). 

  • A steamer transporting cattle from the ports of Texas. 

  • A monster consisting of the upper part of a lion combined with the tail of a fish. 

  • A cow or bull transported by steamer from the ports of Texas. 

How often have the words pinniped and sea lion occurred in a corpus of books? (source: Google Ngram Viewer )