|music a structure consisting of two sections, each being played twice|
in music, the structural pattern of many songs and instrumental pieces, primarily from the 17th to the 19th century, characterized by two complementary, related sections of more or less equal duration that may be represented schematically as ab. In 18th-century compositions, including dance-inspired movements by J.S. Bach and keyboard sonatas by Domenico Scarlatti, the two sections are separated by double bars with repeat signs, so that a proper performance actually yields an aabb structure
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