SDF may refer to:
Computing File formats Spatial Data File, for geodatabases Standard Delay Format, for timing data SQL Server Compact Edition Database File (filename extension: .sdf) Structure data file, for chemical tables Scientific Data Format, a Hierarchical Data Format implementation
Formal computer science Signed distance function (or field), in mathematical applications Syntax Definition Formalism, to describe formal languages
Other uses in computing Software development folder, a physical or virtual container for software project artifacts Synchronous Data Flow, a restriction of Kahn process networks SDF Public Access Unix System, a shared shell provider
Entertainment and media Südtirol Digital Fernsehen, a TV station in South Tyrol, Italy Super Dimensional Fortress, warships in the Robotech/Macross franchise Settlement Defense Front (SDF), an enemy faction of Call of Duty: Infinite Warfare
Organizations Military forces Japan Self-Defense Forces State defense force, US Sudan Defence Force, 1925–1955 Syrian Democratic Forces, 2015–2026
Political parties Sikkim Democratic Front, India Social Democratic Federation (United States), 1936–1956 Social Democratic Federation, UK, 1884–1911 Social Democratic Forum, Hong Kong, 2000 Social Democratic Front (disambiguation), Cameroon and Ghana Socialist Democratic Federation (Japan), 1978–1994
Other organizations Scouts de France, youth group Serb Democratic Forum, Serbs of Croatia Search Dog Foundation, rescue dog training organization
Places Louisville Muhammad Ali International Airport (formerly Standiford Field), Kentucky, US (by IATA code Soquel Demonstration State Forest, California, US
Science Silver diammine fluoride, in dentistry Stromal cell-derived factor (disambiguation), SDF1, SDF1a, etc. Subwavelength-diameter optical fibre Synchronous diaphragmatic flutter or hiccup
Other uses SDF Group (SAME Deutz-Fahr), an Italian-based agricultural machine manufacturer Simplified directional facility, an aviation instrument approach navigational aid Stochastic discount factor, in econometrics