In various popular music styles, riff refers to a brief, relaxed phrase repeated over changing melodies. It may serve as a refrain or melodic figure, often played by the rhythm section instruments or solo instruments that form the basis or accompaniment of a musical composition. Though they are most often found in rock music, Latin, funk and jazz, classical music is also sometimes based on a simple riff, such as Ravel's Boléro. Riffs can be as simple as a tenor saxophone honking a simple, catchy rhythmic figure, or as complex as the riff-based variations in the head arrangements played by the Count Basie Orchestra.
David Brackett (1999) defines riffs as, "...short melodic phrases," while Richard Middleton (1999) defines them as "short rhythmic, melodic, or harmonic figures repeated to form a structural framework". Rikky Rooksby states, "A riff is a short, repeated, memorable musical phrase, often pitched low on the guitar, which focuses much of the energy and excitement of a rock song."
The term riff entered musical slang in the 1920s, and is used primarily in discussion of forms of rock music or jazz. "Most rock musicians use riff as a near-synonym for musical idea." The etymology of the term is not clearly known. Some sources explain riff as an abbreviation for rhythmic figure or refrain. Use of the term has also misleadingly been extended to comedy where riffing is used to mean the verbal exploration of a particular subject, thus moving the meaning away from the original jazz sense of a repeated figure over which the soloist improvises, to instead indicate the improvisation itself: that is, improvising on a melody or progression as one would improvise on a subject by extending a singular thought, idea or inspiration into a bit, or routine. Charlie Parker's 1945 recording Thriving on a Riff may have popularized the term.
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