SPEAK LOW, speak softly; whisper (faintness) [See Faintness]; keep silence [See Taciturnity].
SILENCE; render -mute, - silent; muzzle, muffle, suppress, smother, gag, strike dumb, dumfound or dumbfound, dumfounder or dumbfounder, mum [obs.], drown the voice, put to silence, stop ones mouth, cut one short.
stick in the throat.
ADJECTIVE:
APHONOUS, nonvocal, aphonic, dumb, mute, deaf and dumb, deafdumb; mum; obmutescent [rare], tonguetied; breathless, tongueless, voiceless, speechless, wordless; mute as a -fish, - stockfish, - mackerel; silent (taciturn) [See Taciturnity]; muzzled; inarticulate, inaudible.
CROAKING, raucous, hoarse, husky, dry, hollow, sepulchral, hoarse as a raven; rough.
ADVERB:
WITH BATED BREATH, with the finger on the lips; sotto voce [It.]; in a -low tone, - cracked voice, - broken voice; in broken tones, aside, in an aside.