an animal whose mother is a horse and whose father is a donkey, used especially for transporting goods

a person who agrees to carry illegal drugs into another country in return for payment by the person selling the drugs

These very poor women who are used as mules by drug barons often get long prison sentences. 这些被毒枭雇来越境运送毒品的贫困女子常会被判处长期徒刑。

a woman's shoe or slipper that has no back