ST, St, or St. may refer to:

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 compendium of Catholic philosophy and theology by St. Thomas Aquinas * St or St., abbreviation of "State", especially in the name of a college or university

Businesses and organizations

Transportation

* Germania (airline) (IATA airline designator ST) * Maharashtra State Road Transport Corporation, abbreviated as State Transport * Sound Transit, Central Puget Sound Regional Transit Authority, Washington state, US * Springfield Terminal Railway (Vermont) (railroad reporting mark ST) * Suffolk County Transit, or Suffolk Transit, the bus system serving Suffolk County, New York

Other businesses and organizations

* Statstjänstemannaförbundet, or Swedish Union of Civil Servants, a trade union * The Secret Team#Secret Team, The Secret Team, an alleged covert alliance between the CIA and American industry * STMicroelectronics, a worldwide manufacturer of semiconductors

Geography

* São Tomé and Príncipe (ISO 3166-1 country code ST) ** .st, Internet country code top-level domain for São Tomé and Príncipe * Saxony-Anhalt, a state of Germany * Split, Croatia (vehicle plate code ST) * ST postcode area, Stoke-on-Trent postcode area, United Kingdom * St or St., abbreviation of Saint * St or St., abbreviation of Street * St or St., abbreviation of Strait

Language and typography

* Sesotho language (ISO 639-1 language code "st") * ﬅ, or st, a typographic ligature * Standard Theory in Generative grammar#Frameworks, generative grammar

Science and technology

Computing

* ST connector, a type of optical fiber connector * Atari ST, a personal computer * Prefix of hard disk drives made by Seagate Technology, e.g. ST-506 * 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 *St (terminal emulator), minimalist terminal emulator by suckless.org

Mathematics

* Standard part function, a term used in non-standard analysis

Physics

* Stanton number St, used in physics * Strouhal number St, used in fluid mechanics * String theory

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''

Other uses

* -st, a suffix for an Ordinal number (linguistics), ordinal number, such as 1 or 21 * Saint (St or St.), especially in Christianity * Scheduled Tribes, in India * Ship prefix#Generic (merchant navy) prefixes, Ship prefix for a steam tug * Sine tempore (s.t.), Latin term indicating that a lecture will begin at the exact time; see Academic quarter (class timing) * Striker (association football), a position in association football * ST, a type of Buses in London, London bus