locrian

Locrian is the seventh mode of the diatonic major scale in Western music theory. It is named after the ancient Greek region of Locris. In traditional modal theory, Locrian is one of the ancient church modes, but it is the least used in tonal practice because its tonal center is inherently unstable and its scale contains a diminished fifth.

The Locrian mode has the interval pattern 1, b2, b3, 4, b5, b6, b7. It starts on the seventh degree of the corresponding major scale. For example, in the key of C major, B Locrian uses the notes B-C-D-E-F-G-A-B. The characteristic feature is the diminished fifth between the root and the fifth degree, producing a tense, unresolved quality.

Musical characteristics and usage: Locrian’s lowered second, third, fifth, sixth, and seventh degrees create a dissonant color that resists establishing a strong tonal center. Because of the diminished fifth, it is rarely employed as a stable home key in tonal music. It is mainly discussed in theoretical contexts or used sparingly as a coloristic or experimental device. In some modern or avant-garde practices, composers and improvisers may invoke Locrian concepts to explore altered harmonies and modal color, though it remains uncommon in mainstream repertoire.