Diminuendo
/dɪˌmɪnjuˈendəʊ/
Definition 1 of 2
Pro Tip 1/3Music Dynamics
Used in music to indicate a gradual reduction of volume. 
Note the sheet music's diminuendo marking, urging players to softly fade out.
Pro Tip 2/3Emotional Effect
Creates a sense of calmness or conclusion in music. 
The symphony's final diminuendo left the audience in a reflective silence.
Pro Tip 3/3Orchestration
Signifies orchestral harmony lowering volume together, not just solo instruments. 
The orchestra's diminuendo was well-coordinated, showcasing the conductor's skill.