Which term describes a moderately soft volume in music?

The term that describes a moderately soft volume in music is "mezzo piano." This Italian terminology directly translates to "somewhat soft," indicating a dynamic level that is softer than "mezzo forte" (which means moderately loud) but louder than "piano," which signifies a soft sound.

In musical notation, "mezzo piano" serves as a direction to musicians, guiding them to play at a level of intensity that creates a subtle yet present sound, often used to convey a sense of intimacy or delicacy in a piece. This dynamic marking allows for greater expressive possibilities in compositions, enabling the performer to navigate the nuances of intensity effectively.

Other terms may relate to volume but do not specifically convey the same balance of soft intensity. For instance, "piano" indicates a softer volume than "mezzo piano," while "mezzo forte" denotes a louder dynamic level. "Morendo" refers to a dying away in volume, suggesting a gradual decrease rather than a specific level of sound intensity. Therefore, mezzo piano is the most appropriate choice for describing a moderately soft volume in music.