- AAO stands for American Academy of Ophthalmology
- AAO stands for American Academy of Otolaryngology (Head & Neck Surgery)
- AAO stands for American Association of Orthodontists
- AAO stands for Alpha and Omega
- AAO stands for Against All Odds
- AAO stands for Against All Odds (gaming clan)
- AAO stands for Age At Onset
- AAO stands for American Academy of Optometry
- AAO stands for All As One (various locations)
- AAO stands for Alert and Oriented
- AAO stands for Anglo-Australian Observatory
- AAO stands for America’s Army: Operations (game)
- AAO stands for Alumni Affairs Office (various schools)
- AAO stands for American Academy of Osteopathy
- AAO stands for Academic Affairs Office (various schools)
- AAO stands for Affirmative Action Officer (various locations)
- AAO stands for Archives Association of Ontario
- AAO stands for America’s Army Operations (game)
- AAO stands for Australian Army Orders
- AAO stands for Amino Acid Oxidase
- aaO stands for am angegebenen Ort
- AAO stands for Am Angegebenen Ort (German)
- AAO stands for Approved Acquisition Objective
- AAO stands for Anodic Alumina Oxide
- AAO stands for Association of Aviation Ordnancemen
- AAO stands for Army Acquisition Objective
- AAO stands for Authorized Acquisition Objective
- AAO stands for Administrative Appeal Office (U.S. Citizenship and Immigration Services)
- AAO stands for Association des Amis des Oiseaux (French)
- AAO stands for Awake, Alert and Oriented (medical)
- AAO stands for Association des Archives de l’Ontario (French: Archives Association of Ontario)
- AAO stands for Acetaldehyde Oxime
- AAO stands for Airborne Area of Operation
- AAO stands for Audio, Acoustique et Ondes (French: Audio, Acoustics and Waves)
- AAO stands for Area Audit Office
- AAO stands for Adverse Assumption Obstacle
- AAO stands for Autonomous Aircraft Operations
- AAO stands for American’s Army: Operations (game)
- AAO stands for Army Acquisition Organization
AAO