| Abbreviation | Definition |
|---|---|
| SEMA | Special Electronic Mission Aircraft |
| SEMA | Special Equipment Mission Aircraft |
| SEMI | Special Electromagnetic Interference |
| SEMP | Seawater Electro Magnetic Propulsion |
| SEMP | System Engineering Management Plan |
| SEMS | Standard Embarkation Management System |
| SEMS | Sturm European Military Surplus |
| SEMT | SIEW (Signal Intelligence/ Electronic Warfare) Equipment Maintenance Trainer |
| SEMT | Signal Intelligence/ Electronic Warfare Equipment Maintenance Trainer |
| SEN | Satellite Education Network |
| Sen | Senator |
| SEN | Small Extension Node |
| SENRAD | Serial Number Recognition Accountability System |
| SENS | Small Extension Node Switch |
| SEO | Survivability Enhancement Options |
| SEO | System Engineering Office |
| SEO/SEP | Special Enforcement Operation/special Enforcement Program |
| SEON | Solar Electro- Optical Network |
| SEOP | System Employment and Organizational Plan |
| SEP | Signal Entrance Panel |