The Collaborative International Dictionary of English v.0.48:

Bottlehead \Bot"tle*head`\, n. (Zool.)
   A cetacean allied to the grampus; -- called also
   bottle-nosed whale.
   [1913 Webster]

   Note: There are several species so named, as the pilot
         whales, of the genus Globicephalus, and one or more
         species of Hypero["o]don (Hypero["o]don bidens,
         etc.), found on the European coast. See Blackfish, 1.
         [1913 Webster]