voiceless

adj.

无声的；沉默的；不悦耳的；清音的

1. The old castle was dark and voiceless.
   这座古堡是黑暗和寂静无声的。

On the Properties of Voiceless Fricative Consonants
A cross-linguistic acoustic study of voiceless fricatives
Perception of voiceless fricatives by normal-hearing and hearing-impaired children and adults.
Speech coding in the auditory nerve: III. Voiceless fricative consonants
Closure duration and intervocalic voiced-voiceless distinction in English.
Statistical analysis of word‐initial voiceless obstruents: Preliminary data
Vowel-length differences before voiced and voiceless consonants: An auditory explanation.
Some Cues for the Distinction between Voiced and Voiceless Stops in Initial Position
Generalization of the generation of an MMN by illusory McGurk percepts: voiceless consonants
Contrast and covert contrast: The phonetic development of voiceless sibilant fricatives in English and Japanese toddlers