mule deer

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A brownish-gray deer (Odocoileus hemionus) of western North America, having long mulelike ears, large branching antlers in the male, and usually a white tail with a black tip.

from The Century Dictionary.

• noun The blacktail or black-tailed deer, Cariacus macrotis: so called from the large ears. It is decidedly larger and more stately than the Virginia or white-tailed deer, and is next in size to the wapiti and caribou among the North American Cervidœ.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A deer, found in western North America.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun long-eared deer of western North America with two-pronged antlers