Major and minor

In Western music, the adjectives major and minor may describe an interval, chord, scale, or key. A composition, movement, section, or phrase may also be referred to by its key, including whether that key is major or minor.

The words derive from Latin words meaning "large" and "small," and were originally applied to the intervals between notes, which may be larger or smaller depending on how many semitones (half-steps) they contain. Chords and scales are described as major or minor when they contain the corresponding intervals, usually major or minor thirds.