Ab9 chord
The A-flat dominant ninth chord (abbreviated "Ab9 chord") is a five-note chord consisting of the notes A♭, C, E♭, G♭, and B♭. The chord is formed by adding a major ninth to a A-flat dominant seventh chord.
In practice, the fifth (E♭) is sometimes omitted from the Ab9 chord because it's not always possible to play all notes simultaneously.
Name
A-flat dominant ninth chord
Notes
A♭ C E♭ G♭ B♭
Intervals
1 3 5 ♭7 9
Chord symbol
A♭9
Type
pentad (five-note chord)