Wordnet 3.0
NOUN (1)
1.
small donkey used as a pack animal;
The Collaborative International Dictionary of English v.0.48:
Burro \Bur"ro\, n. [Sp., an ass.] (Zool.)
A donkey. [Southern U.S.]
[1913 Webster]
WordNet (r) 3.0 (2006):
burro
n 1: small donkey used as a pack animal