A eunuch is a male that has been emasculated by the removal of his testicles, penis, or both. This method has been used, historically, for several different purposes, i.e., chiefly to create servants or to mutilate enemies. In the Muslim world, slaves who guarded the harems were castrated while in Imperial China, men who wanted to enter civil service would voluntarily have themselves castrated. In modern parlance, it can be used to describe a weak or overly submissive man. Historically, in Italy (and perhaps elsewhere in Europe), there was once a practice of castrating some pre-pubescent male singers to preserve their soprano voices. These type of singers were known as "Castrati."