THESAURUS
speechless
anaudic, aphasic, aphonic, breathless, brief, brusque, close, close-tongued, closemouthed, concise, curt, dazed, dumb, dumbfounded, dumbstricken, dumbstruck, economical of words, inarticulate, indisposed to talk, laconic, mum, mute, nonplussed, quiet, reserved, shocked, short, silent, snug, sparing of words, stricken dumb, taciturn, terse, thunderstruck, tight-lipped, tongue-tied, tongueless, uncommunicative, unloquacious, untalkative, voiceless, word-bound, wordless
ROGET THESAURUS
speechless
Aphony
N
aphony, aphonia, dumbness, obmutescence, absence of voice, want of voice, dysphony, cacoepy, silence, raucity, harsh voice &c, unmusical voice, falsetto, childish treble mute, dummy, aphonous, dumb, mute, deafmute, deaf and dumb, mum, tongue-tied, breathless, tongueless, voiceless,
speechless, wordless, mute as a fish, mute as a stockfish, mute as a mackerel, silent, muzzled, inarticulate, inaudible, croaking, raucous, hoarse, husky, dry, hollow, sepulchral, hoarse as a raven, rough, with bated breath, with the finger on the lips, sotto voce, in a low tone, in a cracked voice, in a broken voice, vox faucibus haesit.