The Collaborative International Dictionary of English v.0.48:
moose \moose\ (m[=oo]s), n. [A native name; Knisteneaux mouswah;
Algonquin monse. Mackenzie.]
1. (Zool.) A large cervine mammal (Alces alces syn. Alces
machlis, syn Alces Americanus), native of the Northern
United States and Canada. The adult male is about as large
as a horse, and has very large, palmate antlers. It
closely resembles the European elk, and by many Zoologists
is considered the same species. See Elk.
2. A member of the Progressive Party; a Bull Moose.
[Obsolescent. Cant, from the early 1900's.]
[Webster 1913 Suppl. +PJC]
2. [capitalized] A member of the fraternal organization named
Loyal Order of Moose.
Moose bird (Zool.), the Canada jayor whisky jack. See
Moose deer. Same as Moose.
Moose yard (Zool.), a locality where moose, in winter, herd
together in a forest to feed and for mutual protection.