Which term denotes soft sounds in music?

The term that denotes soft sounds in music is "piano." In musical terminology, "piano" specifically instructs musicians to play softly, creating a gentle and subdued tone. It is derived from the Italian word for "soft." This term is integral to dynamics in music, providing the performer with guidance on the volume at which they should play.

The other terms you might encounter in the question serve different musical purposes. "Forte," for example, indicates that the music should be played loudly. "Staccato" refers to a style of playing where notes are sharply detached or separated from each other, contributing to a distinct articulation, rather than to the dynamic level. "Legato," on the other hand, describes a smooth and connected style of playing, where notes are played in a flowing manner without noticeable pauses, which again does not relate to softness. Understanding the specific meanings of these terms helps musicians accurately interpret the dynamics and articulation intended by the composer.