Half Diminished Chord - Minor Seventh Flat Five

The Half Diminished Chord (or Minor Seventh Flat Five, m7b5) is a four-note chord composed of a root, minor third, diminished fifth, and minor seventh. Unlike the diminished seventh chord, which is completely symmetrical, the half-diminished chord has a less tense and more 'melancholic' or 'suspended' sound, while still maintaining a clear resolving impetus. Its sound is often described as 'bluesy', 'jazzy', or 'cinematic', evoking a sense of ambiguity and introspection. It is a cornerstone of jazz, where it serves as the ii degree chord in the ii-V-i progression of minor keys (where the ii is a half-diminished chord), or as a chromatic passing chord. Its diminished fifth gives it enough tension for resolution, while the minor seventh makes it less aggressive than a diminished seventh.

Common Progressions

• iiø7 - V7 - i (the standard jazz progression in a minor key, where the iiø7 serves as preparation for the V7 and then to the minor i)
• As a harmonic passing chord, often between chords a whole tone apart, or as a substitute for altered dominant seventh chords.
• In Latin and Brazilian music, to create a nostalgic or sophisticated atmosphere.