sotto voce

adjective
1
said in a quiet voice so that not everyone can hear
زیر لب, آهسته, ملایم, به‌آهستگی
adverb
1
in a quiet voice so that not everyone can hear
آهسته, زیر لب, نجواگونه, کم‌صدا, زمزمه‌کنان, آرام