All G&A a/c A/D a/r A/S a/s/l C/A See all meanings Idioms and phrases on a collision training course idiom[ C/U ]   audio   plural A’s or As in Western music, the sixth Take note in the size (= series of notes) that commences on the Notice C, or perhaps a list of notes dependant on this ObserveA is usually utilized to denote a little something