D sixth/ninth chord
D6/9 chord for piano with keyboard diagram.
Explanation: The D sixth/ninth is a five note chord. Due to practical circumstances, however, the fifth (A) is often omitted and/or the chord is played inverted. The chord is abbreviated D6/9.
Theory: The D6/9 chord is constructed with a root, a major third, a perfect fifth, a major sixth and a major ninth.
Notes are D - F# - A - B - E