dominant (music)

In music, the dominant is the fifth degree of the scale. For example, in the C major scale (white keys on a piano, starting with C), the dominant is the note G; and the dominant chord uses the notes G, B, and D. In music theory, the dominant chord is symbolized by the Roman numeral V if it is within the major mode (because it is a major triad, for example G-B-D in C major) or v if it is within the minor mode (because it is a minor triad, for example G-B♭-D in C minor, unless of course the B♭ is sharpened to B natural, as will often occur since B natural is the leading tone for the C minor scale).
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