What is the meaning of the word "voice"?

Definitions:

a means or agency by which something is expressed or communicated noun
- the voice of the law
a sound suggestive of a vocal utterance noun
- the noisy voice of the waterfall
allow something to be expressed verb
- I've already voiced my concern.
metonymy for a singer noun
- There is no sound better than a trained voice.
something suggestive of speech in being a medium of expression noun
- the wee small voice of conscience
the ability to speak noun
- I lost my voice.
the distinctive quality or pitch or condition of a person's speech noun
- A shrill voice sounded behind us
the sound made by the vibration of vocal folds modified by the resonance of the vocal tract noun
- Their voice echoed through the building.