1. A gradual diminishing of the sound.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• decresendo,
• decreshendos,
• secrescendo,
• xecrescendo,
• cecrescendo,
• fecrescendo,
• recrescendo,
• eecrescendo,
• dwcrescendo,
• dscrescendo,
• ddcrescendo,
• drcrescendo,
• d4crescendo,
• descrescendo,
• decrescedo,
• defrescence,
• decrescindo,
• decrescede,
• decrescese,
• descrescindo

• decrease,
• Desrosier,
• crescendo,
• decreased.

The adverb form of "decrescendo" is "decrescendo". Since "decrescendo" is already an adverb, it doesn't need a different form.

The adjective form of "decrescendo" is "decrescendo" itself. It is used to describe a gradual decrease in volume or intensity in music.

The plural of the "decrescendo" can be the "decrescendos".

The singular of the "decrescendo" can be the "decrescendo".