aa aa /ˈeɪˈeɪ/

noun

1. A dry form of lava resembling clinkers  ( aa )
   a dry form of lava resembling clinkers
   

 AA

abbreviation

1. Automobile Association (AA) - A UK-based motoring association offering services to its members.  ( AA )
   Automobile Association (AA) - A UK-based motoring association offering services to its members.
   

noun

1. An associate degree in arts  ( AA , Associate in Arts )
   an associate degree in arts
   
2. An international organization that provides a support group for persons trying to overcome alcoholism  ( AA , Alcoholics Anonymous )
   an international organization that provides a support group for persons trying to overcome alcoholism