(n.) The quality or state of being mute; speechlessness.

anaudia aphasia aphonia aphrasia brevity briefness brusqueness conciseness curtness deaf-muteness dumbness economy of words inarticulateness jargon aphasia laconicalness laconism loss of speech motor aphasia mutism obmutescence paranomia paraphasia pauciloquy quietness quietude shortness silence sparingness of words speechlessness taciturnity terseness tonguelessness unloquaciousness untalkativeness voicelessness wordlessness