| Acronym | Definition |
|---|
| SDU | Syddansk Universitet (Denmark) |
| SDU | State Disbursement Unit (child support enforcement) |
| SDU | Service Data Unit |
| SDU | Session Data Unit |
| SDU | Social Development Unit |
| SDU | Staff Development Unit |
| SDU | Sustainable Development Unit |
| SDU | Secondary Dwelling Unit (residence) |
| SDU | Service Delivery Unit |
| SDU | Satellite Data Unit |
| SDU | Sodium Deuranate (uranium salt) |
| SDU | Suleyman Demirel Universitesi (Turkey) |
| SDU | Special Duties Unit (Hong Kong counter-terrorist group) |
| SDU | Special Duty Unit |
| SDU | Rio De Janeiro, Rio De Janeiro, Brazil - Santos Dumont (Airport Code) |
| SDU | Software Development Unit |
| SDU | Scrapbook Design University (est. 1996) |
| SDU | Staatsdrukkerij/Uitgeverij |
| SDU | Subsea Distribution Unit (oil industry) |
| SDU | Secure Data Unit |
| SDU | Students for a Democratic University (Canada) |
| SDU | Standard Dial-Up |
| SDU | Signal Distribution Unit |
| SDU | Selection/Distribution Unit |
| SDU | Seat Display Unit (video monitor control of airline passenger seat) |
| SDU | Saint Dunstan's University (former college, Charlottetown, PEI, Canada) |
| SDU | Sophos Diagnostic Utility |
| SDU | Seat Disconnect Unit |
| SDU | Safety Disarm Unit (military aviation) |
| SDU | Subscriber Data Unit |
| SDU | Shipborne Disk Unit |
| SDU | Signal Detection Unit |
| SDU | Security Device Unit |
| SDU | Self Defense Upgrade |
| SDU | Standalone Display Unit |
| SDU | Structural Damage Underwriter (insurance) |
| SDU | Switch Driver Unit |
| SDU | Storage Device Unit |
| SDU | Super-high Display Unit |