Main Page | See live article | Alphabetical index In Music theory, the leading-tone (called the leading-note outside the US) is the seventh scale degree of any diatonic scale when the distance between it and the tonic is a single semitone. In diatonic scales where there is a whole tone between the seventh scale degree and the tonic, the note is called the sub-tonic. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.