B major ninth chord
Bmaj9 chord for piano with keyboard diagram.
Explanation: The B major ninth is a five note chord and can be regarded as a Bmaj7 with an added ninth. It is often abbreviated as Bmaj9 (should not be confused with B9).
Theory: The Bmaj9 chord is constructed with a root, a major third, a perfect fifth, a major seventh and a major ninth.
Notes: B - D# - F# - A# - C#