SD may refer to:
Military and weaponry
- Smith & Wesson SD, a line of pistol (first made 2010)
- SD radar, an early US Navy radar system
- Southern Cross Decoration (SD), a South African military award
Organisations
Political parties
- Democratic Left (Italy) (2007–2010; Italian: Sinistra Democratica)
- Social Democrats (Slovenia) (founded 1993)
- Solidarity (Brazil) (founded 2012)
- Democratic Party (Poland) (founded 1937; Polish: Stronnictwo Demokratyczne)
- Sweden Democrats (founded 1988)
- Swiss Democrats, Switzerland (renamed 1990; German: Schweizer Demokraten)
- Serbian Right (founded 2018; Serbian: Srpska desnica)
Other organisations
- Sicherheitsdienst, Nazi intelligence service (1931–1945)
- Sisters of the Destitute, a Syro-Malabar Catholic order (founded 1927)
- Sudan Airways (founded 1946; IATA:
SD)
Places
- Sudan (ISO 3166 country code:
SD) - A common abbreviation for the U.S. city of San Diego, California and the San Diego Padres—the city's Major League Baseball team
- Shandong, a province of China
- South Dakota, a US state
- Eswatini (formerly Swaziland; SD on vehicle plates)
Science and technology
Astronomy
- Subdwarf, a class of star
- Surface detector, of cosmic rays at the Pierre Auger Observatory
Electronics and computing
- SD card (Secure Digital), a flash memory card format
- Software Distributor, an HP-UX system
- Standard-definition television
- Super Density Disc, an optical disc format
- Stable Diffusion, a text-to-image generator
Mathematics
- sd (elliptic function), one of Jacobi's elliptic functions
- Standard deviation (SD), a statistical measure of variation
Medicine
- Spasmodic dysphonia, a voice disorder
- Stable disease, a RECIST chemotherapy outcome
Other uses in science and technology
- Service design, holistic design of service experience
- Spiral Dynamics, a model of individual and societal development
- Storm Data, a US meteorological journal
- System dynamics, of nonlinear systems
Other uses
- Sekolah Dasar, term for primary school in Indonesia
- Super D (cycling), a class of mountain bike race
- Super deformed, an art style
- Sindhi language (ISO 639-1 code: sd)
- sine die, Latin, undated (literally without a day)
See also
Topics referred to by the same term
This disambiguation page lists articles associated with the title SD.If an internal link led you here, you may wish to change the link to point directly to the intended article. Category: