(slang) clitic form of o' (contraction of of)

(informal) to (infinitive marker)

The day is lovely.

(obsolete) A person or thing that is preeminent, unique, or which has unusual merit.

(music) A tone one semitone higher than A, denoted A♯. / (music) The key of A sharp major

(idiomatic) Of two or more things, having little difference of any significance between them.

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

(music) A tone one semitone below A, between G and A, denoted A♭. / (music) A key or other mechanism for producing an A-flat. / (music) The key of A-flat major.

(music) The major key with A as its tonic, with the notes A, B, C♯, D, E, F♯, and G♯, the key signature of which has three sharps. / (music) The major chord with a root of A.

(music) The major key with A-flat as its tonic, consisting of the pitches A♭, B♭, C, D♭, E♭, F, and G. / (music) The major chord with a root of A-flat.