| OTA | Obedience Trials Association 
| Others |
| OTA | Occupational Therapy Assistant
| Others |
| OTA | Off-season Team Activities
| Others |
| OTA | Office of Internal Administration
| Others |
| OTA | Office of Tax Analysis
| Others |
| OTA | Office of Tax Appeals
| Others |
| OTA | Office of Technical Assistance
| Others |
| OTA | Office of Technology Alliances
| Others |
| OTA | Office of Technology Assessment
| Others |
| OTA | Office of the Telecommunications Adjudicator
| Others |
| OTA | Office of the Tenant Advocate
| Others |
| OTA | Office of Therapeutics Alliances
| Others |
| OTA | Officer Traning Academy (of India)
| Others |
| OTA | Offroad Trucks Australia
| Others |
| OTA | Offroad Turn Assist
| Others |
| OTA | Ohio Trucking Association
| Others |
| OTA | Oil To Air
| Others |
| OTA | Oil Transmission Automatic
| Others |
| OTA | Oklahoma Trucking Association
| Others |
| OTA | Oklahoma Turnpike Authority
| Others |
| OTA | On-Time Arrival
| Others |
| OTA | One Time Adjustment
| Others |
| OTA | One To All
| Others |
| OTA | One Touch Activation
| Others |
| OTA | One True Army
| Others |
| OTA | Online travel agencies
| Others |
| OTA | Online Travel Agency
| Others |
| OTA | Online Travel Agent
| Others |
| OTA | Online Travel Agents
| Others |
| OTA | Online Trust Alliance
| Others |
| OTA | Ontario Tennis Association
| Others |
| OTA | Ontario Tennis Association's
| Others |
| OTA | Ontario Time Attack
| Others |
| OTA | Ontario Trucking Association
| Others |
| OTA | Open Tools API (Application Programming Interface)
| Others |
| OTA | Open Travel Alliance
| Others |
| OTA | Operational Transconductance Amplifier
| Others |
| OTA | Optical Telescope Assembly
| Others |
| OTA | Optical Transmit Asymmetry
| Others |
| OTA | Optical Trapping Applications
| Others |
| OTA | Optical Tube Assembly
| Others |
| OTA | Optional Taco Accessories
| Others |
| OTA | Oracle Training Administration
| Others |
| OTA | Orchard Training Area
| Others |
| OTA | Oregon Telecommunications Association
| Others |
| OTA | Oregon Truck Association
| Others |
| OTA | Oregon Truck Associations
| Others |
| OTA | Oregon Trucking Association
| Others |
| OTA | Oregon Trucking Associations
| Others |
| OTA | Organic Trade Association
| Others |
| OTA | Organizatia Turismului Si Automobilului
| Others |
| OTA | Organized Team Activities
| Others |
| OTA | Organized Team Activity
| Others |
| OTA | Origin Technology Age
| Others |
| OTA | Ortho-Tolidine-Arsenite
| Others |
| OTA | Orthodontic Technicians Association
| Others |
| OTA | Orthopaedic Trauma Association
| Others |
| OTA | Oshawa Truck Assembly
| Others |
| OTA | Other Transaction Authority
| Others |
| OTA | Over The Air
| Others |
| OTA | Over-the-air
| Others |
| OTA | Overall Track
| Others |
| OTA | Oxford Text Archive
| Others |
| OTA | Turkish, Ottoman (1500 - 1928)
| Others |