\Por"poise\, n. [OE. porpeys, OF. porpeis, literally,
hog fish, from L. porcus swine + piscis fish. See {Pork}, and
{Fish}.]
1. (Zo["o]l.) Any small cetacean of the genus {Phoc[ae]na},
   especially {P. communis}, or {P. phoc[ae]na}, of Europe,
   and the closely allied American species ({P. Americana}).
   The color is dusky or blackish above, paler beneath. They
   are closely allied to the dolphins, but have a shorter
   snout. Called also {harbor porpoise}, {herring hag},
   {puffing pig}, and {snuffer}.
2. (Zo["o]l.) A true dolphin ({Delphinus}); -- often so
   called by sailors.
{Skunk porpoise}, or {Bay porpoise} (Zo["o]l.), a North
   American porpoise ({Lagenorhynchus acutus}), larger than
   the common species, and with broad stripes of white and
   yellow on the sides. See Illustration in Appendix.