In places:

• San Francisco, California, a city with a population of more than 730,000, located on the West Coast of the United States.
• The San Francisco Giants, a franchise in the MLB
• The San Francisco 49ers, a franchise in the NFL
• Sioux Falls, South Dakota, a city with a population of over 140,000, the center of the Midwest.
• Sofia, Bulgaria, the capital city of Bulgaria

In things:

• Speculative fiction, term coined by Robert A. Heinlein as a synonym for science fiction, but now refers to a literary genre which includes science fiction. Also abbreviated "spec-fic," "S-F", or "sf".
• Science Fiction, Literary genre, also abbreviated as "Sci-Fi".
• Scuderia Ferrari, the racing division of the Ferrari automobile company
• Significant figures (in mathematics)
• Spontaneous fission, a nuclear decay route in which a superheavy nucleus splits into two.
• SourceForge, a collaborative software development management system
• Special forces, small, highly trained and specialised military units
• Security Forces, US Air Force's version of MP and ground infantry
• Stade Français Paris, a French rugby union team
• Statsforetak, a type of Norwegian state enterprise
• Six Flags, a chain of theme parks
• Svensk Filmindustri, the Swedish Film Industry
• Tassili Airlines, IATA airline designator
• Salad Fingers, a flash animation created by David Firth
• Salmon farming, farming of salmon (see Fish farming)
• Selle Français, French breed of horse
• Superleague Formula, a new motor racing formula mixing football (soccer)and motorsports

In acronyms:

• Socialistisk Folkeparti, the Danish Socialist People's Party.
• Sinn Féin, an Irish political party.
• Schweizer Fernsehen, or Swiss Television, a German-language television network in Switzerland.
• Science fiction, a literary genre

In music:

• Sforzando, musical notation for a sudden, strong emphasis
• Senses Fail a hardcore punk band from New Jersey
• Switchfoot, an alt-rock band
• Scaterd Few, a Christian punk band
• Shadows Fall, a metal band
• Sarcastic Front a hardcore punk band from Czech Republic

In video games:

• Stellar frontier, a game by Stardock in 1997
• Soldier Front, a tactical first-person shooter game, licensed by ijji
• SourceForts, a modification of the Half-Life 2 first-person shooter game
• Street Fighter (series), a series of electronic fighting games by the company Capcom
• Syphon Filter, a series of action-shooter games on the Sony Playstation consoles
• Strategy First, a video game software company
• Star Fox (series), a video game series by Nintendo

In defunct uses:

• Finland as an abbreviation for Suomi-Finland. Suomi is the Finnish-language name for Finland.
• Suomen Filmiteollisuus, a Finnish film production company.
• The Hull classification symbol for a "Fleet Submarine" in the United States Navy

In other:

• Steve Francis, an NBA player for the Houston Rockets
• Small Forward, a basketball position
• Sacrifice fly, baseball terminology