Sotto voce

sotto voce \SAH-toh-VOH-chee\, adverb or adjective:
1. Spoken low or in an undertone, as not to be overheard.
2. (Music) In very soft tones. Used chiefly as a direction.

Behind the scenes, however, were sotto voce grumblings that Kohl was perhaps hanging on too long and that the party might be better off if he were to step aside and hand the candidacy to popular majority leader Wolfgang Schauble.
-- Jordan Bonfante, "The Challenger", Time, March 16, 1998