Wiktionary
quietening
n. The act of making something quieter. vb. (present participle of quieten English)
WordNet
Usage examples of "quietening".
Less easy was the quietening of the concerns of the majority, not least because they were his own also.
His voice was frail, almost quavery, yet it filled the small church, quietening the crowd more successfully than any threats from the guards.
A pause as it probed round with immature senses, its giddy thoughts quietening down.
By which time it was middle to late afternoon, the light came slanting through the trees, and the forest was slowly quietening down .