| Acronym | Definition |
|---|
| COSMOS | Computer System for Mainframe Operations |
| COSMOS | Conseil Social du Mouvement Sportif (French: Social Council of Sports Movement) |
| COSMOS | California State Summer School for Mathematics and Science |
| COSMOS | C# Open Source Managed Operating System (software) |
| COSMOS | Consortium of Organizations for Strong Motion Observation Systems |
| COSMOS | Computerized Safety, Maintenance and Operation Systems of Shinkansen (Japan) |
| COSMOS | Complementary Symmetry Metal Oxide Semiconductor |
| COSMOS | Component Service Model with Semantics |
| COSMOS | Centralization Of Supply Management Operations |
| COSMOS | Compound Semiconductor Material on Silicon (research project) |
| COSMOS | Collections Of Southern Maryland Online System |
| COSMOS | Counter Surge Mission Mortar System |
| COSMOS | Computer System for Switch Mainframe Operations |
| COSMOS | Coast Survey Marine Observation System |
| COSMOS | Complementary Silicon Metal-Oxide Semiconductor (RCA) |
| COSMOS | Computational Optimization of Small Molecular Structures |