What is the term for the left hand in musical expression?

The term for the left hand in musical expression is commonly referred to as "mano sinistra." In musical notation, especially in piano music, terms in Italian are frequently used to indicate which hand plays a particular passage. "Mano" translates to "hand" in English, and "sinistra" means "left." This terminology helps performers communicate effectively regarding which hand should be used for specific sections of music, facilitating a more expressive and accurate performance.

On the other hand, the other terms provided refer to different concepts. "Mano destra" translates to "right hand," indicating the hand used for playing melodies or higher notes in pieces. "Braccio destro" and "braccio sinistro" refer to "right arm" and "left arm," respectively, which are not typically used in the context of musical expression for hand instruction on instruments. Therefore, "mano sinistra" is the appropriate term when discussing the left hand in music.