| Acronym | Definition |
|---|
| OSTA | Optical Storage Technology Association |
| OSTA | Osteoporosis Self-Assessment Tool for Asians |
| OSTA | Office of Space and Terrestrial Applications (US NASA; now OAST) |
| OSTA | Old Spanish Trail Association |
| OSTA | Open Standard Telecom Architecture (hardware platform) |
| OSTA | Occupational Skill Testing Authority (China) |
| OSTA | Ohio State Trappers Association (est. 1940) |
| OSTA | Oklahoma Science Teachers Association (Stillwater, OK) |
| OSTA | Oberlin Student Theater Association (Oberlin College; Ohio) |
| OSTA | Oregon Substitute Teachers Association |