Guitar chords in the key of A:
Chord Adim notes: A, Eb, A and C. You must leave out the 6th and 1st strings.
The string 5 (A) is left open.
Adim - A diminished triad guitar chord's alternative names: A°, A-5, Am-5, and Adim. See also: Adim7 and Am7b5.
1(A), b3(C), b5(D#/Eb).