A-sharp major

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun 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.
• noun music the major chord with a root of A-sharp