Synonyms and related words :
brief, brusque, close, close-tongued, closemouthed, concise, curt, dumb, economical of words, indisposed to talk, laconic, mum, mute, quiet, short, silent, snug, sparing of words, speechless, taciturn, terse, tight-lipped, tongue-tied, unloquacious, word-bound, wordless