What does "calando" mean in musical terms?

In musical terminology, "calando" signifies a gradual decrease in both tempo and dynamics, typically leading to a more subdued or softer performance. This term captures the essence of music that suggests a fading out or a diminishing sound, which aligns perfectly with the idea of "dying away." When a composer instructs musicians to play "calando," it indicates an intentional softening of the music, inviting a more introspective or gentle vibe.

This understanding reflects the nuances of musical expression and the ways in which performers interpret markings to effectively convey emotional content in their playing. The other options refer to different musical techniques or effects that do not match the specific definition of "calando."