| Abbreviation | Definition |
|---|---|
| SNLA | Scottish National Liberation Army |
| SNLC | Senior North Atlantic Treaty Organization (NATO) Logisticians Conference |
| SNM | Said Named Marine |
| SNM | Show No Mercy |
| SNM | Single Nation Model |
| SNM | Special Nuclear Material |
| SNM | System Notification Message |
| SNMP | Soviet Nuclear Missile Program |
| SNOI | Signal Not of Interest |
| SNOK | Secondary Next of Kin |
| SNONI | Senior Naval Officer Northern Ireland |
| SNR | Sonar |
| SNR | Sub-Net Relay |
| SNT | Serial Number Tracking |
| SNTES | Standalone NMD Test and Exercise System |
| SNU | Series Not Used |
| SNV | Vultee Aircraft Corporation Valiant, Trainer Aircraft |
| SO | Safety Observer |
| SO | Safety Officer |
| SO | Silent Observer |