fadingnoise
nounUK /ˈfeɪdɪŋ nɔɪz/
US /ˈfeɪdɪŋ nɔɪz/
A sound that slowly gets quieter until you can't hear it.
The fading noise of the train lulled the baby to sleep.
OTHER MEANINGS
2. A radio signal that weakens as the distance grows.
The fading noise on the radio told us we were far from the city.
3. Background sound that gradually blends into silence.
A fading noise of rain drifted away as the storm passed.
4. The last soft sounds of something ending.
We listened to the fading noise of the party as guests left.