Wah-wah | A musical effect achieved on brass instruments by alternately applying and removing a mute and on an electric guitar by controlling the output from the amplifier with a pedal. Also the pedal used to produce such an effect on an electric guitar.
Walking bass | A bassline in 4/4 time with a note played on each beat of the bar, typically moving up or down a scale in small steps; often includes a mixture of scale tones, arpeggios, and passing tones to outline the chord progression of a song, alternately rising and falling in pitch over several bars.
Waltz | A dance in triple time, with the accent falling on the first beat of each measure.
Whammy bar | A lever attached to the bridge of an electric guitar that can slacken or elongate the strings temporarily, changing the pitch to create a tremolo or pitch bend effect. (Also tremolo arm or tremolo bar.)
Wheel fiddle | (See hurdy gurdy.)
Whistle | A clear, high-pitched sound made by forcing breath through a small hole between partly closed lips, or between one’s teeth. Also a small wind instrument that produces such a sound from a stream of forced air.
Whole note | A note with the time value of two half notes or four quarter notes; represented my a note head with no stem; the longest note now in common use. (Also semibreve.)
Whole rest | A rest with the time value of two half rests or four quarter rests. (Also semibreve rest.)
Whole step | (See whole-tone.)
Wind ensemble | (See concert band.)
Wind quintet | The music for (or an ensemble of) five wind instruments (usually including a flute, oboe, clarinet, bassoon, and French horn). (Also woodwind quintet.)
Wolf | (See wolf tone.)
Wolf tone | A loud, harsh noise produced when a played note matches the natural resonating frequency of the body of a musical instrument. (Also wolf.)
Wood finish | The protective coating covering the surface of a musical instrument; sometimes paint, but usually lacquer.
Woodwind quintet | (See wind quintet.)
Word play | The witty use of the meanings and ambiguities of words (especially puns).
World music | Traditional music from the developing world. Also Western popular music that incorporates elements of such music.
Worried note | In blues music, a note that is played or sung with a slight quiver and deliberately out of tune.