Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top.
GmMaj7 is G, Bb, D and F# — Gm with the major seventh added on top.
It sounds tense and wrong-footed. A minor triad carrying a major seventh: the semitone under the root over a minor chord is the first bar of a line cliché.

| G | Bb | D | F# |
|---|---|---|---|
| 1 | ♭3 | 5 | 7 |
Minor tonic — the tonic of the melodic minor.
Also written GmM7, Gm(maj7), G-Δ7 or GminMaj7. The same chord either way; which spelling you meet depends on who wrote the chart.
Root, third and seventh. The third and seventh, the guide tones, are what make the chord major, minor or dominant, so the fifth can go: it says nothing the symbol needs.
Three notes means a spare string, which is the real point. Put a tension on it.
GmMaj7 has 4 of them, on the bottom three strings, strings 6-4-3, the low-middle three and strings 5-3-2, from open position up to the 10th — all in one inversion, so the bass note never moves. The one to learn first is the G shape at the nut.
Start with 310032 — no barre and 2 open strings. 1 of the 7 shapes here sits in open position. 1 of the 7 needs a barre. Together they cover the neck from the 1st fret to the 15th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| 310032 | open position | G, root position | F# | 2 open strings |
| xx5332 | 2nd fret | G, root position | F# | all fretted |
| 354333 | 3rd fret | G, root position | G | barred |
| xx5776 | 5th fret | G, root position | Bb | all fretted |
| x-10-8-7-7-x | 7th fret | G, root position | F# | all fretted |
| x-10-12-11-11-10 | 10th fret | G, root position | D | all fretted |
| x-13-12-12-15-14 | 12th fret | Bb, 1st inversion | F# | all fretted |
The same notes rebuilt from scratch give 13 drop 2, 9 drop 3 and 4 open string voicings, each on its own page.
Tensions. A shell of GmMaj7, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (A), the 11 (C) and the 13 (E).
How you get to it. The turn that lands on GmMaj7 is Am7♭5 to D7♭9: the ii and the V of G minor, which is where a minor tonic is usually arrived at rather than simply begun on.
Every note of GmMaj7 is in G harmonic minor and G melodic minor.
Change one note of GmMaj7 and you have Gm (drop the major seventh), Gmaj7 (the minor third becomes a major third), Gm6 (the major seventh becomes a sixth), Gm7 (the major seventh becomes a flat seventh), GmMaj7b5 (the fifth becomes a flat fifth) or GmMaj9 (add the ninth).
GmMaj7 is a minor chord — root, minor third, fifth. Minor chords on every root.
On GmMaj7’s sound and use this page follows Mark Levine, The Jazz Theory Book (Sher Music, 1995). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.