bur·ro (bûrō, brō, bŭrō)
n. pl. bur·ros
1. A small donkey, especially one used as a pack animal.
2. Slang A drug smuggler who swallows bags filled with a drug, especially heroin or cocaine, to avoid detection by drug enforcement officers or customs officials.
[Spanish, back-formation from borrico, donkey, from Vulgar Latin *burrīcus, variant of Late Latin būricus, burricus, small horse, of unknown origin.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.