| OAA | Oakdale Athletic Association 
| Others |
| OAA | Oakland Activities Association
| Others |
| OAA | Obstetric Anaesthetists Association
| Others |
| OAA | Obstetric Anaesthetists' Association
| Others |
| OAA | Office of Academic Advising
| Others |
| OAA | Office of Academic Affairs
| Others |
| OAA | Office of Academic Affiliations
| Others |
| OAA | Office of the Administrative Assistant
| Others |
| OAA | Office on African Affairs
| Others |
| OAA | Ogden, Allen, and Associates
| Others |
| OAA | Ohio Achievement Assessment
| Others |
| OAA | Ohio Achievement Assessments
| Others |
| OAA | Ohio Assment Achiments
| Others |
| OAA | Ohio Aviation Association
| Others |
| OAA | Okinawa Association of America
| Others |
| OAA | Oklahoma Agents Alliance
| Others |
| OAA | Old Age Assistance
| Others |
| OAA | Older Americans Act
| Others |
| OAA | Oman Automobile Association
| Others |
| OAA | One Against All
| Others |
| OAA | Online Application for Admission
| Others |
| OAA | Online Auto Auction
| Others |
| OAA | Ontario Association of Archers
| Others |
| OAA | Ontario Association of Architects
| Others |
| OAA | Open Agent Architecture
| Others |
| OAA | Open Arcade Architecture
| Others |
| OAA | Open Automotive Alliance
| Others |
| OAA | Opticians Association of America
| Others |
| OAA | Optometrists Association Australia
| Others |
| OAA | Oracle Advanced Analytics
| Others |
| OAA | Orbiter Access Arm
| Others |
| OAA | Orbiter Alternate Airfield
| Others |
| OAA | Organic Acidemia Association
| Others |
| OAA | Oriental Astronomical Association
| Others |
| OAA | Otaku Anime Academy
| Others |
| OAA | Other Agency
| Others |
| OAA | Other Agency Accounts
| Others |
| OAA | Other Aquatic Animals
| Others |
| OAA | Over Analyzers Anonymous
| Others |
| OAA | Over-the-Air Activation
| Others |
| OAA | Overly aggressive anon
| Others |
| OAA | OxAloAcetate
| Others |
| OAA | oxaloacetate aKG alpha
| Others |
| OAA | Oxford Aviation Academy
| Others |