submediant n : (music) the sixth note of a major or minor scale (or the third below the tonic)
- (music) the sixth note of a scale, shown as VI.
In music, the submediant is the sixth tonal degree of the diatonic scale. It is so called because it is a step below the mediantonic, in contrast to the mediant being a third above the tonic. It is the mediant of the subdominant triad. In the C major scale (white keys on a piano, starting on C), the submediant is the note A; and the submediant chord uses the notes A, C, and E. In music theory, the submediant chord is symbolized by the Roman numeral vi if it is within the major mode (because it is a minor triad, for example A-C-E in C major) or VI if it is within the minor mode (because it is a major triad, for example A♭-C-E♭ in C minor).
The submediant function is easily explained in reference to jazz music, where it is used in the "ice cream change" or "blues for alice" progression, which moves from the tonic through the submediant on the way to the ubiquitous II-V-I Jazz sequence (part of the cycle of fifths). The progression's consistency is amplified by the submediant's fifth-relationship above the supertonic. This submediant role -- in which it essentially extends from the tonic as a way of "passing" to a subdominant (IV) or supertonic (II) harmony, is as common in popular and classical music as it is in jazz, or any other musical language related to Western European tonality.
"Submediant" also refers to a relationship of musical keys. For example, relative to the key of C major, the key of A major (or A minor) is the submediant. Modulation (change of key) to the submediant is relatively rare, compared with, say, modulation to the dominant, and gives a feeling of relaxation. Susan McClary says that modulation to the lowered submediant (in C: A♭) represents a dream-like state of escape.
In German theory derived from Hugo Riemann the submediant in major is considered the tonic parallel (US relative), Tp, and the minor the subdominant parallel, sP.
submediant in Spanish: Submediante
submediant in French: Sus-dominante
submediant in Italian: Sopradominante
submediant in Hebrew: סובמדיאנטה