C Minor Ninth chord (Cm9) on the guitar fretboard

The C Minor Ninth chord (Cm9) is made of C (the root), Eb (minor third), G (perfect fifth, optional), Bb (minor seventh) and D (major ninth). The fretboard shows every one of them across the neck in standard tuning (E A D G B E), and plays them back so you can hear the chord.

The minor ninth is a minor seventh with a ninth stacked above, and the fifth is optional. Its notes repeat in several overlapping shapes on the neck. It sits between the minor seventh and the minor eleventh.