[[Dimini]][[shed]]: Lowered by a half-step. See 'Alteration'. [[Diminished triad]]: Triad composed of two stacked minor thirds, root, minor third, and diminished fifth. [[Diminished seventh (o7)]]: Chord composed of 4 notes, stacked in minor thirds. The symbol is a small raised circle. Since an additional minor third on top will be the octave of the bottom note, inversions of a o7 will have the same interval structure in other words, they will also be diminished 7th chords in their own right. The extensions of a o7 are a ninth (or whole step) above each chord tone. Effective modern voicing requires using at least one extension; plain o7 chords sound remarkably old-fashioned. If the chord tones and extensions are put together within an octave, the diminished scale results. Often called just 'diminished' with '7th' being implied. [[Diminished Scale]]: A scale of 8 notes to the octave in alternating whole-steps and half-steps. There are just three different diminished scales. Quite a complicated system of voicings and motivic patterns for diminished has been developed by modern players.