What Does It Mean?
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From our dictionary:
sot•to vo•ce
(sot'O vO'chE; It.sôt'tô vô'che),
in a low, soft voice so as not to be overheard.
(sot'O vO'chE; It.sôt'tô vô'che),
in a low, soft voice so as not to be overheard.