The Dorian mode is a minor scale with a natural 6th. It has a jazzy, funky, soulful quality - darker than major but brighter than natural minor. One of the most commonly used modes in jazz, funk, and blues.
Scale Formula
1 2 b3 4 5 6 b7 - minor with natural 6. Semitone pattern: W H W W W H W
Fretboard (C Dorian)
Toggle to interval view to spot the natural 6 - it is the one note that separates Dorian from Aeolian (natural minor). Find it relative to the root on each string pair.
Common Chords
Minor triad (1 b3 5), Minor 7th (1 b3 5 b7), Minor 6th (1 b3 5 6), Minor 9th (1 b3 5 b7 9).
Diatonic Harmony
Improvisation Context
Play over minor 7th chords, especially when they function as a ii chord. The natural 6 is the characteristic note that distinguishes Dorian from Aeolian.
Characteristic Note
The natural 6th is what makes Dorian brighter than Aeolian. It sits 4 frets up on the next string from the root (a major 6th = 9 semitones). Emphasize it in your lines to bring out the Dorian color - it is the note that gives funk and soul vamps their signature warmth over minor chords.
Practice
Play C Dorian against a Cm7 drone. Then play C Aeolian (natural minor) over the same drone and listen for the difference - the single note change (A vs Ab) shifts the entire mood. Improvise phrases that emphasize the 6th, landing on it as a target note. Try a classic Dorian vamp: Cm7 to Dm7 (i to ii in C Dorian).