acronym for Associate in Arts, a college degree granted for successful completion of a two-year course of study in arts or general topics. [WordNet 1.5]
aa, abbr.
1 Automobile Association.
2 Alcoholics Anonymous.
3 Mil. anti-aircraft.
4 Brit. (of films) classified as suitable for persons of over 14 years.
Usage
Now replaced by PG.
Also see definition of "aa" in Bible Study Dictionaries