The full form of AA can vary depending on the context. Here are a few possibilities:

• Alcoholics Anonymous: A fellowship of people who share their experience, strength, and hope with each other that they may solve their common problem and help others to recover from alcoholism. https://www.aa.org/
• Associate of Arts: An undergraduate academic degree.
• Anti-Aircraft: Used to describe weapons designed to attack enemy aircraft from the ground.
• Affirmative Action: Policies and practices designed to address past and present discrimination against specific groups.

To determine the specific meaning of AA, you would need to consider the context in which it is being used.