The note next above the keynote; the second of the scale.

the note or chord on the second degree of the major scale. This is often marked with the Roman numeral II.

(music) the second note of a diatonic scale

The second degree of the diatonic scale.

The second scale degree in the Western major or minor scales.

The second degree of the major or minor scale. Also, the name of the triad built on the second degree of the scale, indicated by II in a major scale and iio in a minor scale.

In music or music theory, the supertonic is the second degree or note of a diatonic scale (in other words, immediately "above" the tonic). For example, in the C major scale (white keys on a piano, starting on C), the supertonic is the note D; and the supertonic chord uses the notes D, F, and A. In music theory, the supertonic chord is symbolized by the Roman numeral II if major (for example D-F♯-A in C major with a sharpened third) or ii if minor (for example D-F-A in C major without any chromatic alteration).