Cm9

Cm9 denotes a C minor ninth chord, a five-note harmony used in jazz, pop, and related styles. In its standard form it comprises the notes C, Eb, G, Bb, and D. The D is the ninth above C, while Bb is the minor seventh of the chord. Musically, it is built from a C minor triad (C, Eb, G) with a minor seventh (Bb) and a major ninth (D added on top).

In notation, Cm9 is typically written as Cm9 or Cmin9. If the seventh is omitted, the chord may be labeled Cm(add9). Because the 9th often appears above the root, many voicings place the D near the top, while the 5th (G) can be omitted in compact versions. Common realizations include root-position voicings such as C Eb G Bb D, and inverted or drop-voicings (for example, voicings that reposition the upper voices while keeping the essential notes).

Usage and context: Cm9 is frequently found in jazz standards and other contemporary music as a color harmony within a minor-key setting. It can function as a i9 sonority in minor keys or appear as a rich extension within broader progressions, including ii–V type sequences or as a substitutive color for a plain minor seventh chord. The chord often resolves smoothly to related chords such as Cm7, Fm, or Ab major, depending on voice-leading and the surrounding harmonic plan.

Notes: Cm9 is distinct from Cm(add9) in that Cm9 includes the seventh (Bb); omitting the seventh yields the add9 variant.