voicelessness vs susurration

voicelessness and susurration both are nouns.

Word	Noun	Adjective	Verb	Adverb
voicelessness	Yes	No	No	No
susurration	Yes	No	No	No

As nouns, voicelessness and susurration are synonyms defined as:

voicelessness and susurration: speaking softly without vibration of the vocal cords

Other synonyms of voicelessness include whisper, whispering.

voicelessness (noun)	susurration (noun)
having no voice in the management or control of affairs	speaking softly without vibration of the vocal cords
speaking softly without vibration of the vocal cords	the indistinct sound of people whispering
(phonetics, of a consonant) The property of being spoken without vibration of the vocal cords, as [t], [s], or [f].
a disorder of the vocal organs that results in the loss of voice