Musical symmetry

thumb|Title page of Franz Rigler's "Three Rondos" (1790) thumb|First page of the manuscript for Mozart's [[Adagio and Rondo for glass harmonica, flute, oboe, viola and cello]] The rondo or rondeau is a musical form that contains a principal theme (sometimes called the "refrain") which alternates with one or more contrasting themes (generally called "episodes", but also referred to as "digressions" or "couplets"). Some possible patterns include: ABACA, ABACAB, ABACBA, or ABACABA (with the letter 'A' representing the refrain).

musical scale with twelve pitches, each a semitone above or below another

scale in which each note is separated from its neighbors by a whole tone; in 12-tone equal temperament, there are only two complementary whole tone scales

musical term with meanings with respect to intervals, chords, voices, and melodies

musical scale with 8 pitches per octave

chord with an augmented interval

musical modes or scales that fulfill specific criteria relating to their symmetry and the repetition of their interval groups

seventh chord composed of a root note, together with a minor third, a diminished fifth, and a diminished seventh; e.g. C–E♭–G♭–B𝄫

passage of notes played in reverse

a sequence containing each tone in the chromatic scale (or some other scale of interest), used in serialist musical composition