A riff is an ostinato figure: a repeated chord progression or melodic figure, often played by the rhythm section instruments, that forms the basis or accompaniment of a rock music or jazz composition.
The term "riff" is sometimes regarded as slang, and is used primarily in discussion of forms of rock music or jazz.
David Brackett (1999) defines them as, "short melodic phrases," while Richard Middleton (1999) defines them as, "short rhythmic, melodic, or harmonic figures repeated to form a structural framework."
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