Geography

• Southwest, one of the 4 ordinal directions, in weather forecasting and geography

Companies

• Smith & Wesson
• Southern Water, a water company of England
• Southern Winds Airlines, a defunct Argentine airline
• the IATA code for Air Namibia
• Southwest_Airlines, a U.S. airline

Military

• Surface Warfare, a designation fo Enlisted Surface Warfare Specialists
• Superweapon

People

Computing & Electronics

• Semantic Web
• Shareware
• Shortwave
• Software
• Solid Works
• Subwoofer

Sport

• Sand Wedge
• Stampede Wrestling

Language and Slang

• Love the show, the real meaning of the oft-used compliment "SW's" on the Sarah Kennedy breakfast show on BBC Radio 2
• Sarcasm Warning
• Street Walker
• Swahili language (ISO 639 alpha-2, sw)

Other

• Band 3, a protein
• Samurai Warriors
• Snow White, a story written by Brothers Grimm
• Socialist Worker
• sport wagon
• Star Wars
• station wagon (American English), a car body style
• a USCS symbol for well graded sand