Definitions:
originally: a measure of capacity for liquid, used especially in spain and portugal and varying according to locality and the nature of the contents. in later use: a large cask for wine or other liquids, the capacity of which varies according to the contents and locality.

a small wine flask made of leather or goatskin which may be slung over the shoulder or chest, having a narrow nozzle from which wine is squirted directly into the mouth.

a boot, especially for riding. also (in plural): leather leggings or similar protective coverings for the legs.