OST

OST may refer to:

Music

 * Original soundtrack, recorded sound accompanying a production such as a film
 * O.S.T., an alias of electronic musician Chris Douglas
 * O.S.T. (album), by the People Under the Stairs

Science and technology

 * Object Storage Target in computing, used by the Lustre file system an others
 * Oligosaccharyltransferase, an enzyme
 * Open-space technology, for organising meetings
 * Open Systems Theory, a form of sociotechnical systems pioneered by Fred Emery
 * Orbit stabiliser theorem in mathematics
 * Offline Storage Table, a Microsoft file format
 * OST Family (organic solute transporter) of genes
 * Origins Space Telescope, a space telescope mission
 * Open Source Threat, any software demonstrating a device vulnerability that is open-source

Organizations

 * Office of Science and Technology, a British government agency
 * Office of Secure Transportation, a US government agency
 * Order of the Solar Temple, French esoteric cult
 * Organisation Socialiste des Travailleurs, the Socialist Workers Organisation of Senegal
 * Outer Space Treaty, a treaty regulating international law in outer space.

Places

 * Ostend–Bruges International Airport, Belgium, IATA code
 * Old Spanish Trail (auto trail)

Other uses

 * Ost (surname)