from The American Heritage® Dictionary of the English Language, 4th Edition
- adv. In soft tones, so as not to be overheard; in an undertone: "There were aspersions cast, sotto voce, but knees quickly folded into curtsies when introductions were in order” ( Barbara Lazear Ascher).
- adv. Music In very soft tones. Used chiefly as a direction.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. In soft tones; quiet.
- adj. soft (can be used of instruments other than the voice, such as pianos)
- adv. (speaking) quietly
- adv. (spoken or played) softly (can be used of instruments other than the voice, such as pianos)
- n. A direction in a score that a passage in a piece should be played softly (or sung 'under the voice', when applied to vocal music).
from the GNU version of the Collaborative International Dictionary of English
- With a restrained voice or moderate force; in an undertone.
- Spoken low or in an undertone.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adv. in an undertone
Italian : sotto, under + voce, voice.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Italian, literally "low voice". (Wiktionary)