roe deer

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A rather small, delicately formed Eurasian deer (Capreolus capreolus) having short branched antlers in the male and a brownish coat.

Wiktionary

1. n. A small, nimble Eurasian deer with short three-pointed antlers, no visible tail, a white rump patch, and a reddish summer coat that turns grey in winter (Capreolus capreolus).