# ST

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
* 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)
* 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

## 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, such as 1st or 21st
* Saint (St or St.), especially in Christianity
* Scheduled Tribes, in India
* 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 London bus
* ST, a court-ordered pseudonym used during a British court case; see Sudiksha Thirumalesh case