Open English Wordnet
Nouns
(n)whisper, whispering, susurration, voicelessnessspeaking softly without vibration of the vocal cords
(n)voicelessnesshaving no voice in the management or control of affairs“the voicelessness of those who live in situations of hopelessness”
(n)voicelessness(phonetics, of a consonant) The property of being spoken without vibration of the vocal cords, as /t/, /s/, or /f/.“Instead, he plans to maintain voicelessness of the consonant and an unintended consequence of that effort is a pitch perturbation following release.”