|1.||a. a central or determining principle in a speech, literary work, etc|
|b. (as modifier): a keynote speech|
|2.||the note upon which a scale or key is based; tonic|
|3.||to deliver a keynote address to (a political convention, etc)|
|4.||to outline (political issues, policy, etc) in or as in a keynote address|
in music, the first note (degree) of any diatonic (e.g., major or minor) scale. It is the most important degree of the scale, serving as the focus for both melody and harmony. The term tonic may also refer to the tonic triad, the chord built in thirds from the tonic note (as C-E-G in C major). See also tonality.
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