| Acronym | Meaning |
| STRATCOM | United States Strategic Command |
| STRICOM | U.S. Army Simulation |
| STRIVE | Synthetic Tactical Real-time Interactive Virtual Environment |
| STSM | Senior Technical Staff Member |
| STUKA | Sturzkampfflugzeug (German WWII Dive Bomber) |
| SU | Soviet Union (ISO 3166 Digram; Obsolete 1992) - Sudan (FIPS 10-4 Country Code) |
| SU | Sundanese Language (ISO 639-1 Code) |
| SUB | Student Union Building |
| SUD | Subject Under Discussion |
| SUI | Sonic User Interface |
| SUN | Soviet Union (ISO 3166 Trigram; Obsolete 1992) |
| SUN | Sundanese Language (ISO 639-2 Code) |
| SUNY | State University Of New York (usually Pronounced Sue-knee) |
| SUR | Suriname (ISO 3166 Trigram) |
| SURTASS | Surveillance Towed Array Sensor System |
| SUV | Sport Utility Vehicle |
| SV | El Salvador (ISO 3166 Digram) -Sportverein (German For Sport Association |
| SV | Swedish Language (ISO 639-1 Code) |
| SVC | Secondary Visual Cortex |
| SVD | Singular Value Decomposition - Snaiperskaya Vintovka Dragunova (??????????? ???????? ????????? |
| SVD | Svenska Dagbladet (Swedish Newspaper) |
| SVG | Scalable Vector Graphics |
| SVK | Slovakia (ISO 3166 Trigram) |
| SVM | Support Vector Machine (artificial Intelligence) |
| SVN | Slovenia (ISO 3166 Trigram) |
| SVO | Subject |
| SW | South-West - Sweden (FIPS 10-4 Country Code) |
| SW | Swahili Language (ISO 639-1 Code) |
| SWA | Secure Web Access - South-West Asia |
| SWA | Swahili Language (ISO 639-2 Code) |
| SWALK | Sealed With A Loving Kiss |
| SWAN | System For Wearable Audio Navigation |
| SWAP | Surface Waters Acidification Programme |
| SWAPO | South-West Africa People's Organisation |
| SWAT | Special Weapons And Tactics |
| SWE | Sweden (ISO 3166 Trigram) |
| SWE | Swedish Language (ISO 639-2 Code) |
| SWF | Shockwave Flash File (swiff) - Single White Female |
| SWG | Surface Warfare Group - Symbology Working Group |
| SWHR | Society For Women's Health Research |
| SWIG | Simplified Wrapper And Interface Generator |
| SWIR | Short Wave InfraRed (ss-why-are Or Swhirr) |
| SWLABR | -(a) She Walks Like A Bearded Rainbow - Cream Song (Bruce |
| SWORD | Subjective WORkload Dominance |
| SWORDS | Special Weapons Observation Reconnaissance Detection System |
| SWOT | Strengths |
| SWP | Special Working Party (swipp) - Systematic Westing Plan (a Plan Of Periodic Westing Of Shares Or Mutual Funds Worth A Fixed Amount Of Money) - Skill With Prizes (UK Pub Quiz Machines - Quality Titles Include: Pub Quiz |
| SWT | Sea Water Tank |
| SWZ | Swaziland (ISO 3166 Trigram) |
| SX | Sonic X |