It refers to the scale with the same notes as that of a major scale in another key.
Example, minor is the relative minor of major as both of them have the same notes.
G minor: G A Bb C D Eb F G
Bb major: Bb C D Eb F G A Bb
It refers to the scale with the same notes as that of a major scale in another key.
Example, minor is the relative minor of major as both of them have the same notes.
G minor: G A Bb C D Eb F G
Bb major: Bb C D Eb F G A Bb