A-sharp-major Definition

(music) The major key with A-sharp as its tonic and the notes A#, B#, C##, D#, E#, F##, G##. Such high numbers of accidentals (especially double sharps) are undesirable. Therefore, it is usually scored and referred to as its enharmonic equivalent; B-flat major.

(music) The major chord with a root of A-sharp.