ST

ST, St, or St. may refer to:

• -st, a suffix for an ordinal numeral, such as 1^st or 21^st
• St, abbreviation of "saint" (British and Commonwealth usage)
• St., abbreviation of "saint" (elsewhere)
• St., abbreviation of "street", e.g. in addresses

Arts and entertainment

• Stanza, in poetry
• Suicidal Tendencies, an American heavy metal/hardcore punk band
• Star Trek, a science-fiction media franchise
• Summa Theologica, a 13th-century compendium of Catholic philosophy and theology by St. Thomas Aquinas
• "S.T. the Space Traveler", a 1990 episode (S8 E8 / #97) of 1983 TV series Alvin and the Chipmunks
• Stranger Things, a 2016–2025 Netflix sci-fi horror series

Places and transportation

• São Tomé and Príncipe
• Saxony-Anhalt (ISO 3166 code DE-ST), a state of Germany
• ST postcode area, United Kingdom, centered around Stoke-on-Trent
• St., abbreviation of "strait"
• ST, the prefix in vehicle registration plates of Croatia for the region centered around Split, Croatia
• ST, the registration prefix for aviation in Sudan
• ST, the ship prefix for a steam tug or steam trawler

Transportation companies

• ST, the IATA airline designator for German airline Germania (airline)
• ST, the railroad reporting mark for American railroad Springfield Terminal Railway (Vermont)
• Sound Transit, a shortened form of Central Puget Sound Regional Transit Authority in the U.S. state of Washington
• State Transport, a shortened form of Maharashtra State Road Transport Corporation of India
• Suffolk Transit, a shortened form of Suffolk County Transit, the bus system serving Suffolk County, New York, U.S.
• Stouffville line (ST), of the GO Transit rail network in Ontario, Canada

Language and typography

• st, the ISO 639-1 language code for the Sesotho language
• ſt or st, typographic ligatures
• Standard Theory in generative grammar

Science and technology

• ST Engineering, a global technology, defense, and engineering group headquartered in Singapore

Electronics and computing

• ST connector, Straight Tip optical fiber connector
• Seagate Technology, an American data storage company, whose hard disk drives are named with the prefix "ST-"
• STMicroelectronics, a worldwide manufacturer of semiconductors
• Atari ST, a 1985 line of personal computers
• Internet Stream Protocol, an experimental Internet protocol
• Structured text, a high-level programming language that syntactically resembles Pascal and is designed for programmable logic controllers (PLC)
• .st, the Internet country code top-level domain (ccTLD) for São Tomé and Príncipe

Mathematics

• Standard part function, a mapping from hyperreal to real numbers
• Such that (s.t.), a phrase preceding a condition predicate

Physics

• String theory, a model of subatomic structure
• Spherical tokamak or spherical torus (ST), a type of fusion power device

Dimensionless numbers in fluid dynamics

• Stanton number (St), relating to thermodynamics of fluid
• Strouhal number (St), describing oscillating flow mechanisms

Units of measurement

• Stokes (unit) (St), a CGS unit of kinematic viscosity
• Stone (weight) (st.), a unit of mass used in the British Isles and other countries

Medicine

• ST segment, the part of an electrocardiogram connecting the QRS complex and the T wave
• Sulfotransferase, enzymes that catalyze the transfer of a sulfo group
• Heat-stable enterotoxin, secretory peptides produced by some bacterial strains, such as enterotoxigenic Escherichia coli

Education

• s.t., abbreviation of sine tempore, a Latin term used to indicate that a lecture will begin at the exact time; see academic quarter (class timing)
• St., abbreviation of "state", especially in the name of a college or university (e.g. Penn St.)

Law

• Scheduled Tribes, in India
• ST, the court-ordered pseudonym used in the Sudiksha Thirumalesh case

Other uses

• Striker (association football), a position in association football
• Statstjänstemannaförbundet, or Swedish Union of Civil Servants, a trade union

See also

• ΣΤ (disambiguation) (sigma tau)
• STST (disambiguation)
• STFC (disambiguation) for uses of ST F.C.
• All pages with titles beginning with ST
• All pages with titles beginning with St