mute

a deaf person who is unable to speak

a device used to soften the tone of a musical instrument

deaden (a sound or noise), especially by wrapping

expressed without speech; "a mute appeal"; "a silent curse"; "best grief is tongueless"- Emily Dickinson; "the words stopped at her lips unsounded"; "unspoken grief"; "choking exasperation and wordless shame"- Thomas Wolfe

unable to speak because of hereditary deafness