- producing a muted, bawling sound like that of a trumpet with the hand moved momentarily over the bell: a wah-wah effect on a synthesizer; a guitar with a wah-wah pedal.
- a sound or effect like the muted sound of a trumpet, especially in music.
- an electronic device or attachment to produce such a sound, often used with an electric guitar.
- the sound made by a trumpet, cornet, etc, when the bell is alternately covered and uncovered: much used in jazz
- an electronic attachment for an electric guitar, etc, that simulates this effect
