douille

A douille is a French term that can refer to several distinct objects, primarily a socket or a casing. In the context of firearms, a douille refers to the cartridge case, the metallic or plastic shell that holds the propellant and projectile. This casing is ejected after firing. The term can also be used for a socket in electrical fittings, such as a light bulb socket, which is the part into which the bulb screws or fits. In a more general sense, particularly in French vernacular, "douille" can also refer to a type of error or blunder, often a foolish or clumsy mistake. This idiomatic usage is common in everyday conversation. The specific meaning of douille is therefore dependent on the context in which it is used, whether it pertains to ammunition, electrical components, or an informal description of an error.