The Collaborative International Dictionary of English v.0.48:
Mutely \Mute"ly\, adv. Without uttering words or sounds; in a mute manner; silently. [1913 Webster]WordNet (r) 3.0 (2006):
mutely adv 1: without speaking; "he sat mutely next to her" [syn: mutely, wordlessly, silently, taciturnly]