What is a performer’s interpretation of a piece of music called?

A performer’s interpretation of a piece of music is referred to as "expression." This term captures how a musician conveys emotions, dynamics, and articulations specific to a piece, reflecting their personal insights and feelings. Expression is crucial to performance, as it goes beyond just playing the right notes; it involves the nuances and subtleties that make the music resonate with an audience.

While performance refers to the act of presenting the music, it does not specifically denote the nuanced interpretation that comes with expression. Technique typically refers to the skill level and mastery of an instrument and does not encompass the deeper emotional aspects of a performance. Style relates to the broader characteristics that define a musical genre or the manner in which music is typically played, which might include historical or cultural elements but does not encompass an individual musician’s unique interpretation of a specific work. Thus, "expression" best describes a performer’s personal approach to interpreting a piece of music.