Quaver v. i. : To tremble; to vibrate; to shake.

Quaver v. i. : Especially, to shake the voice; to utter or form sound with rapid or tremulous vibrations, as in singing; also, to trill on a musical instrument

Quaver v. t. : To utter with quavers.

Quaver n. : A shake, or rapid and tremulous vibration, of the voice, or of an instrument of music.

Quaver n. : An eighth note. See Eighth.

Example:
How to stop a weird nervous "Quaver" in your voice when talking to new people?

Taxonomy
eighth note, stems, quaver, flags, free encyclopedia, curve, fusa, Figure 1, facing down, eighth rest, duration, note stem, middle line, German, Achtelnote, Language, croma, pausa.

Defination from the web:
quaver (other English-speaking countries) is a musical note played for one eighth the duration of a whole note, hence the name. ... A related symbol is the "eighth rest" (or "quaver rest"), which denotes a silence for the same duration. ...