What does AA. stand for?

What does AA. mean?

AA	Active Page Business » Accounting
AA	Advanced Alloy Academic & Science » Chemistry
AA	Automatic Adjust Academic & Science » Electronics
AA	Asian Avenue Community
AA	Anatomical Adaptation Medical » Physiology
AA	Affordability Analysis Governmental » Military
AA	Argument Analysis Academic & Science » Mathematics
AA	Another Ah Miscellaneous » Toastmasters
AA	Activity Approach Community » Educational
AA	Alternative Armies Miscellaneous » Hobbies
AA	Aptitude Area Governmental » Military
AA	Ancient Arts Academic & Science » Universities
AA	Audible Audiobook Community » Media
AA	Ann Arbor Railroad Regional » Railroads
AA	Abbreviated Analysis Governmental » Military
AA	Against Actuals Business » Stock Exchange
AA	Air Abrasion Business » Products
AA	Activities and Attitudes Community » Law
AA	Ancient Anguish Community » Sports
AA	Auto Answer Computing » Telecom
AA	America's Answer Governmental » US Government
AA	Amazon Alliance Miscellaneous » Science Fiction
AA	Absolutely Alright Miscellaneous » Funnies
AA	Algorithmic Architecture Governmental » Military
AA	Author's Alteration Community » Media