dī​yǔ

to whisper

低语 低語 dī​yǔ
to whisper verb
to speak in a low voice; to mutter or murmur

When someone whispers in your ear, that’s 30 decibels.

murmur
a soft, quiet sound of speaking; an aside

Frequency

Movie subtitles
1.43 per million appears in 1% of films
Written text
0.981 per million

Sources