sort by Rank | Alpha
| Possible Meanings | Rank |
| Office of Academic Assistance | **** |
| Ocean Atlantic Agency | **** |
| Oxford Aviation Academy | **** |
| Office of Agricultural Affairs | **** |
| Oregon Acupuncture Association | **** |
| Office on African Affairs | **** |
| Order of Australia Association | **** |
| Ottawa Art Association | *** |
| On Aging Awards | *** |
| Orientation Association Area | *** |
| Oceania Athletics Association | *** |
| Olympia Artisan Alliance | *** |
| On Aging Administers | *** |
| Originally Approved Amount | *** |
| Of Area Agencies | *** |
| Older American Act | *** |
| Ogunquit Art Association | *** |
| Office of Academic Affairs | *** |
| Outdoor Advertising Association | *** |
| Office of Administrative Appeals | *** |
| Oceanic and Atmospheric Administration | *** |
| Office Activation Assistant | *** |
| Ontario Aquaculture Association | *** |
| optical amplifiers and | *** |
| Obstetric Anaesthetists Association | *** |
| Ottawa Angel Alliance | *** |
| Ohio Auctioneers Association | *** |
| Office Automation Asst | *** |
| Outside Agency Assist | *** |
| Oklahoma Aerospace Alliance | *** |
| Oshawa Art Association | *** |
| Ontario Architects Association | *** |
| Orphans Against AIDS | *** |
| Office of Aboriginal Affairs | *** |
| Oriental Astronomical Association | *** |
| Office of Academic Advising | *** |
| Oceania Athletic Association | *** |
| Ontario Association of Archivists | *** |
| Okinawa Association of America | *** |
| Office of Alumni Affairs | *** |
| Orthoptic Association of Australia | *** |
| Organic Acid Additives | *** |
| Optometrists Association Australia | *** |
| Olney Art Association | *** |
| Orient Airlines Association | *** |
| Office Administrative Assistant | ** |
| Orange Art Association | ** |
| oleic acid anilide | ** |
| organic acid anhydrides | ** |
| ovarian ascorbic acid | ** |
| Open Access Archiving | ** |
| Ontario Association of Archers | ** |
| Oklahoma Aggregates Association | ** |
| On Arrival Accommodation | ** |
| Oman Athletic Association | ** |
| Office of Automotive Affairs | ** |
| Ottawa Animal Advocates | ** |
| diet+/-oral anti-diabetic agents | ** |
| Older American's Act | ** |
| oxolinic acid-esculin-azide | ** |
| Optometrists Association of Australia | ** |
| Osaka Action Agenda | ** |
| Office of Assessment and Accountability | ** |
| Ohio Academy of Audiology | ** |
| Organic Agriculture Association | ** |
| Of the Oriental Astronomical Association | ** |
| Office of the Assistant Administrator | ** |
| Orthopaedic Associates of Allentown | ** |
| Ohio Apartment Association | ** |
| Oman Automobile Association | ** |
| Okaloosa Arts Alliance | ** |
| Oklahoma Agents Alliance | ** |
| Oregon Aquaculture Association | ** |
| Office of Academics Affairs | ** |
| Otaku Anime Academy | ** |
| Open Aikido Association | ** |
| Ohio Aviation Association | ** |
| Ogden Allen and Associates | ** |
| Oglethorpe Astronomical Association | ** |
| Office of AIDS Administration | ** |
| Office of Acquisitions and Assistance | ** |
| Organization for Amateur Astronomers | ** |
| Oakdale Athletic Association | ** |
| Of Organic Agriculture Address | ** |
| Optometry Association of Australia | ** |
| Other Aberdeen Areas | ** |
| Oregon Auctioneers Association | ** |
| Office of the Associate Administrator | ** |
| Old Achimotan Association | ** |
| Oral Antidiabetic Agents | ** |
| Oceanside Airport Association | ** |
| Ontario Association of Architectural | ** |
| Office of Academic Administration | ** |
| Office of Appeals | ** |
| Open Acceptable Action | ** |
| Opticians Assoc of America | ** |
| Overseas Advertising Agency | ** |
| Oxford Architectural Antiques | ** |
| Oregon Academy of Audiology | * |
| Oregon Ambulance Association | * |
| Organization and Administration | * |
| Ozark Adventist Academy | * |
| Ohio Auctioneer Association | * |
| Older Adult Association | * |
| Orthodox Authors Association | * |
| Orthopedic Associates of Arkansas | * |
| Ostriches Anonymous Association | * |
| Outdoor Advertising Awards | * |
| Ohio Archers Association | * |
| Oregon Accreditation Alliance | * |
| Oromo Artists Association | * |
| Otolaryngology Associates of Arlington | * |
| Of Academic Administrators | * |
| Oklahoma Airsoft Association | * |
| Oklahoma Aquatic Alliance | * |
| Oregon Apartment Association | * |
| Organ Allocation Areas | * |
| Other Appropriate Action | * |
| Oceanic and Atmosphere Administration | * |
| Ohio AfterSchool Association | * |
| Online and Analysis Applications | * |
| Ontario ACTT Association | * |
| Operative Assistance Authority | * |
| Orbiter Alternate Airfield | * |
| Organizations of Africans in the Americas | * |
| Owners Association Alliance | * |
| Oaths And Affirmations | * |
| Older Americans Amendments | * |
| Office of Affirmative Action | * |
| Office Of Assistant Administrator | * |
| Office of the Associate Administ | * |
| Office of the Associate Attorney | * |
| Office of the Association Attorney | * |
| Ohio Aggregates Association | * |
| Oifig an Ard Aighne | * |
| Olympic Airways Aircraft | * |
| Ontario Archaeological Association | * |
| Onuma And Associates | * |
| Ortho Active Appliances | * |
| Osservatorio Astrofisico di Arce | * |
| Outdoor Adventures in Alaska | * |