| Abbreviation | Definition |
|---|---|
| SQQ | Surfact ship sonar system |
| SQQ-32 | Variable Depth Minehunting Sonar |
| SQQ-89 | Undersea Warfare Combat System |
| SQR | Software Quality Record |
| SQR | Software Quality Review |
| SQR-18 | Sonar Tactical Towed Array System |
| SQS | Still Quiet Silence |
| SQS | Submarine Sonar |
| SQS-53 | Submarine Sonar |
| SQT | Skill Qualification Test |
| SQT | Software Qualification Test |
| SQT | Software Quality Training |
| SQT | System Qualification Testing |
| SQUAD | Squadron |
| SQUAD | Strong, QUick, and Dangerous |
| S-Quad | Silent Sound Spread Spectrum |
| SQUID | uperconducting Quantum Interference Device |
| SQV | Software Quality Verification |
| SQW | Software Quality Workshop |
| SQX | Software Quality Unknown |