| Acronym | Definition |
|---|
| SSSD | System Security Services Daemon (Fedora software) |
| SSSD | Scranton State School for the Deaf (Pennsylvania) |
| SSSD | Single Sided Single Density |
| SSSD | Siloam Springs School District (Arkansas) |
| SSSD | Steamboat Springs School District (Colorado) |
| SSSD | Shanksville-Stonycreek School District (Pennsylvania) |
| SSSD | Steamin' Schneeman and the Screamin' Demons (band) |
| SSSD | Strike and Surveillance Systems Division (Northrop Grumman Corporation) |
| SSSD | Scandinavian Society for the Study of Diabetes |
| SSSD | SUPSHIP San Diego |
| SSSD | South Side School District (Pennsylvania) |
| SSSD | Sovereign-Class Super Star Destroyer (Star Wars) |
| SSSD | Simple Sound for Small Devices |
| SSSD | Student Special Services District |
| SSSD | Small Systems Software Development (Kingsport, Tennessee) |
| SSSD | Seven Segment Sequence Driver |
| SSSD | Ship's System Staging Diagram |
| SSSD | Single Stroke Solid Die |
| SSSD | Same Stuff Same Day |
| SSSD | Self-Securing Storage Device |