A eleventh chords
A11 chord for piano presented by keyboard diagrams.
Explanation: The A eleventh is a six note chord. Due to practical circumstances and/or dissonance the third (C#) is omitted in A11 and/or the chord is played inverted. The chord is often abbreviated as A11.
Theory: The A eleventh chord is constructed by adding a third to a ninth chord.
Notes: A - C# - E - G - B - D