| Rank | Abbreviation | Meaning |
|---|
| ***** | OTCA | Omnibus Trade and Competitiveness Act of 1988
| |
| *** | OTCA | L-2-oxothiazolidine-4-carboxylic acid
| |
| *** | OTCA | Overseas Technical Cooperation Agency (est. 1962; Japan)
| |
| ** | OTCA | Over the Counter Analgesics
| |
| ** | OTCA | Organização do Tratado de Cooperação Amazônica (Portuguese: Amazon Cooperation Treaty Organization)
| |
| ** | OTCA | Ottawa Tourism and Convention Authority (Canada)
| |
| ** | OTCA | Office of Technical and Customer Assistance (Rhode Island)
| |
| ** | OTCA | Old Town Commercial Association
| |
| * | OTCA | 2-Oxo-L-thiazolidine-4-carboxylic acid
| |
| * | OTCA | Ontario Tobacco Control Act
| |
| * | OTCA | Office of Technology Cooperation and Assistance
| |
| * | OTCA | Oregon Tort Claims Act
| |
| * | OTCA | Ohio Tennis Coaches Association
| |
| * | OTCA | Office of Technology Assessment
| |
| * | OTCA | Overseas Technology Cooperation Agency
| |
| * | OTCA | Ontario Tire Collectors Association
| |
| * | OTCA | onset tuberculosis, clinically active
| |
| * | OTCA | intraoperative transluminal coronary angioplasty
| |
| * | OTCA | Operative transluminal coronary angioplasty
| |