Cmmaj7 is the C minor major 7 chord. Its notes are C, E♭, G and B. A minor triad with a major seventh, useful for descending minor lines.
How to play Cmmaj7
Barre chord
fret 3, A shape
x35443
Barre tip: the long bar marked BARRE means one finger presses several strings at once. Lay it flat just behind the fret, press with the bony outer edge rather than the soft middle, and keep your thumb behind the neck. Pick each string one at a time and nudge the finger until none of them buzz.
Numbers show frets from the low E string to the high e string; x means don't play that string.
What's in Cmmaj7
C1
E♭♭3
G5
B7
Formula
1 · ♭3 · 5 · 7
Also written
Cm(maj7), CmM7
Chord type
Minor major 7
Cmmaj7 notes across the neck
Every C, E♭, G and B on the first 12 frets. The filled dots are the root, C. Build your own shape from any nearby group.