tritone
Various forms of the tritone.
Locrian mode
music
Locrian mode, in Western music, the melodic mode with a pitch series corresponding to that produced by the white keys of the piano within a B–B octave. The Locrian mode and its plagal (lower-register) counterpart, the Hypolocrian mode, existed in principal long before they were mentioned by the Swiss humanist Henricus Glareanus in his landmark music treatise Dodecachordon (1547). In that work Glareanus expanded the standing system of church modes to accommodate the increasingly common...