| OMAA | Abu Dhabi Nadia International, United Arab Emirat 
| Others |
| OMAA | Office for Multicultural and Academic Affairs
| Others |
| OMAA | Ogunquit Museum of American Art
| Others |
| OMAA | Oh My Aching A**
| Others |
| OMAA | Ohio Municipal Attorneys Association
| Others |
| OMAA | Oman Museum Across Ages
| Others |
| OMAA | Ontario Metis Aboriginal Association
| Others |
| OMAA | Ontario Municipal Administrators Association
| Others |
| OMAA | Oracle Maximum Availability Architecture
| Others |
| OMAA | Oral Medicine Academy of Australasia
| Others |
| OMAA | Orientation and Mobility Association of Australasia
| Others |
| OMAA | Oxford Martial Arts Academy
| Others |