(music) A wolf tone or wolf note; an unpleasant tone produced when a note matches the natural resonating frequency of the body of a musical instrument, the quality of which may be likened to the howl of a wolf.
This cello has a terrible wolf on the D string around 'F'.
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[German; from the howling sound]
a (1) :dissonance in some chords on organs, pianos, or other instruments with fixed tones tuned by unequal temperament (2) :an instance of such dissonance
b :a harshness due to faulty vibration in various tones in a bowed instrument
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