| Rank | Abbreviation | Meaning |
|---|
| ***** | RTSA | Railways and Transport Safety Act
| |
| ***** | RTSA | Release to Service Authority
| |
| ***** | RTSA | Radiative Transfer in Stellar Atmospheres
| |
| ***** | RTSA | Road Transport and Safety Agency
| |
| ***** | RTSA | Real-Time Simulation and Animation
| |
| **** | RTSA | Rail Travel Service Agent
| |
| **** | RTSA | Rail Technical Society of Australasia
| |
| **** | RTSA | Reaction Time Sensitivity Analysis
| |
| **** | RTSA | Railway Technical Society of Australasia
| |
| **** | RTSA | Road Traffic Safety Association
| |
| *** | RTSA | Residential Treatment Services of Alamance
| |
| *** | RTSA | Real Time Structure Analysis
| |
| *** | RTSA | Retail Traders and Shopkeepers Association
| |
| *** | RTSA | Real-Time Spectrum Analyzer
| |
| *** | RTSA | Real Time Systems Analysis
| |
| *** | RTSA | Reaching and Teaching Stressed and Anxious
| |
| ** | RTSA | Real Time Structural Analysis
| |
| ** | RTSA | Real-Time Structured Analysis
| |
| ** | RTSA | Remote Technical Support Advantage
| |
| ** | RTSA | Radio Tuning Software Application
| |
| ** | RTSA | Rail Travellers Service Agents
| |
| ** | RTSA | Released Transportation Service Agreement
| |
| * | RTSA | Radioecology at The Swedish Agriculture
| |
| * | RTSA | Real Time Security Awareness
| |
| * | RTSA | Real Time Situational Awareness
| |