| S&T | Surf and Turf 
| Others |
| S&TD | Science and Technology Directorate
| Others |
| S&TI | Scientific and Technical Intelligence
| Others |
| S&V | Sepientia et Veritas
| Others |
| S&W | Smith & Wesson
| Others |
| S&W | Speed and Wheels
| Others |
| S'more | Some More
| Others |
| S'mores | Some Mores
| Others |
| S'vnts/Qtrs | Servants Quarters
| Others |
| S-1 | Army Adjutant/Personnel Staff at the Battalion/Brigade level
| Others |
| S-1 | First Sacral Vertebra
| Others |
| S-1 | first sacral vertebrum
| Others |
| S-2 | Army Intelligence Staff at the Battalion/Brigade level
| Others |
| S-2 | Battalion or Brigade Intelligence Staff Officer (Army
| Others |
| S-2 | Marine Corps Battalion or Regiment)
| Others |
| S-2 | Second Sacral Vertebra
| Others |
| S-3 | Army Operations Staff at the Battalion/Brigade level
| Others |
| S-3 | Battalion or Brigade Operations Staff Officer (Army
| Others |
| S-4 | Army Logistics Staff at the Battalion/Brigade level
| Others |
| S-4 | Battalion or Brigade Logistics Staff Officer (Army
| Others |
| S-5 | Army Civilian Affairs/Public Affairs Staff at the Battalion/Brigade level
| Others |
| S-6 | Army Communications and Information Management Staff at the Battalion/Brigade Level
| Others |
| S-7 | Army Inter-Component Integration Staff at the Battalion/Brigade Level
| Others |
| S-8 | Army Resource Management Staff at the Battalion/Brigade Level
| Others |
| S-9 | Army Facilities Management Staff at the Battalion/Brigade Level
| Others |
| S-A | Sinoatrial Node
| Others |
| S-A | Spencer-Attix
| Others |
| S-Abf | SysRq
| Others |
| S-ARM | Standard-Antiradiation Missile
| Others |
| S-B | Soviet-Bloc
| Others |
| S-B | Stanford-Binet
| Others |
| S-BAHN | StadtschnellBAHN
| Others |
| S-Band | 1,500 to 5,200 MegaHertz
| Others |
| S-BD | S-BanD
| Others |
| S-Box | Substitution-box
| Others |
| S-CAR | School for Conflict Analysis and Resolution
| Others |
| S-Dance | Swords Dance
| Others |
| S-Day | Day The President Authorizes Selective Reserve Call-Up
| Others |
| S-HTTP | Secure Hyper Text Transfer Protocol
| Others |
| S-IBN | Star - Isolated Bonding Network
| Others |
| S-ICD | Sal-Intra-Compressed Dioxins
| Others |
| S-J | Stevens-Johnson syndrome
| Others |
| S-K | Saltonstall-Kennedy Promote and Develop American Fisheries Bill
| Others |
| S-LSA | Special Light Sport Aircraft
| Others |
| S-M | IEEE Software Magazine
| Others |
| S-MD | Split Master Bedroom
| Others |
| S-MOWG | Super Management Operations Working Group
| Others |
| S-N | Stress Number
| Others |
| S-Quad | Silent Sound Spread Spectrum
| Others |
| S-TYPE | Silicaceous (Asteroid)
| Others |