What Does "Dominant" Mean?

The dominant is the fifth scale degree of a key, and by extension the chord built on it — the V chord. In C major, the dominant note is G and the dominant chord is G (or G7). Its defining trait: it pulls. No sound in tonal music demands resolution to the tonic more strongly than V–I.

Why the pull is so strong

Two forces stack up. The dominant's root sits a perfect fifth above the tonic — the tightest acoustic relationship after the octave. And the dominant chord contains the leading tone, a half step under the tonic, straining upward. Add the seventh (making it a dominant seventh chord) and you plant a tritone inside that must resolve. That's why 12-bar blues turns around on the V, and why nearly every classical phrase ends V–I.

Three meanings, one word

Guitarists hit "dominant" in three related uses:

1. The degree — scale degree 5.
2. The function — chords doing "pull home" duty in a progression.
3. The chord quality — "dominant seventh" (C7, G7): a major triad plus flat seventh, named because it naturally occurs on degree 5. A "secondary dominant" borrows this pull for other chords.

Related terms

• Tonic — where the dominant resolves
• Subdominant — degree 4, the step away from home
• Cadence — the V–I moment itself