| Acronym | Definition |
|---|
| SUD | Substance Use Disorder |
| SUD | Santos dos Últimos Dias (Portuguese: Latter Day Saints) |
| SUD | Sustainable Urban Development (various organizations) |
| SUD | Sudan Airways (ICAO code) |
| SUD | Special Utility District (water systems) |
| SUD | Signed under Duress (contract law) |
| SUD | Stretched Upper Deck (aircraft modifications) |
| SUD | Start up Disk |
| SUD | Single Use Device |
| SUD | Surface Design |
| SUD | Sudden Unexplained Death |
| SUD | Solidaires Unitaires et Démocratiques (France) |
| SUD | Safe Use Determination |
| SUD | Solidarité, Urgence, Développement (French: Solidarity, Urgency, Development) |
| SUD | Single User Device |
| SUD | Sololatecos Unidos Por El Desarrollo (Spanish: Solola States For Development; Guatemala) |
| SUD | Stopping Underage Drinking (Washington, DC) |
| SUD | System Under Design |
| SUD | Schedule of Unreconciled Differences (financial auditing) |
| SUD | Stress Ulcer Disease |
| SUD | Single-User Detector |
| SUD | Schedule of Unadjusted Differences (accounting, auditing) |