from
The Collaborative International Dictionary of English v.0.48
Porpoise \Por"poise\, n. [OE. porpeys, OF. porpeis, literally,
hog fish, from L. porcus swine + piscis fish. See {Pork}, and
{Fish}.]
1. (Zool.) Any small cetacean of the genus {Phoc[ae]na},
especially {Phoc[ae]na communis}, or {Phoc[ae]na
phoc[ae]na}, of Europe, and the closely allied American
species ({Phoc[ae]na 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}.
[1913 Webster]
2. (Zool.) A true dolphin ({Delphinus}); -- often so called
by sailors.
[1913 Webster]
{Skunk porpoise}, or {Bay porpoise} (Zool.), 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.
[1913 Webster]