All G&A a/c A/D a/r A/S a/s/l C/A See all meanings Idioms and phrases over a collision course idiom[ C/U ]   audio   plural A’s or As in Western songs, the sixth Observe in the dimensions (= number of notes) that commences on the Observe C, or possibly a set of notes depending on this note⟨a⟩ may be the third-most-normally used letter in En