Dominant
in music, the fifth tone of the diatonic scale, and which assumes the character of a keynote itself when there is a modulation into the first sharp remove. Thus, G is the dominant of the scale C, and D the dominant of the scale of G.
Dominant chord, in music, that which is formed by grouping three tones, rising gradually by intervals of a third from the dominant or fifth tone of the scale. It occurs almost invariably immediately before the tonic chord which closes the perfect cadence.