# OSI

OSI may refer to:

## Places

* Osijek Airport (IATA code: OSI), an airport in Croatia
* Ősi, a village in Veszprém county, Hungary
* Oši, an archaeological site in Semigallia, Latvia
* Osi, a village in Ido-Osi, Ekiti State, Nigeria
* Osi, Ekiti LGA.Kwara State, Nigeria

## Organizations

* Oblates of St. Joseph, a Roman Catholic Religious order that uses the postnominal initials O.S.I.
* Open Source Initiative, an organization dedicated to promoting open source software
* Open Society Institute, a private charitable foundation established by George Soros to promote open societies around the world
* Open Society Institute-Baltimore, a locally based foundation that is part of Open Society Foundations
* Open Space Institute, an organization that seeks to preserve scenic, natural and historic landscapes
* Ordnance Survey International, a former subsidiary of the UK Ordnance Survey mapping agency
* Ordnance Survey Ireland (Suirbhéireacht Ordanáis Éireann)
* Otto-Suhr-Institut, the political-science institute of the Free University of Berlin

### Companies

* OSI Group, an American holding company of meat processors that service the retail and food service industries
* OSI Pharmaceuticals, an American pharmaceutical company
* OSI Restaurant Partners, the restaurant and entertainment group that includes Outback Steakhouse
* OSI Systems, a company that manufactures security scanners and medical equipment based in California
* OSIsoft, a privately held company that develops device connectivity software
* Objective Systems Integrators, a company that provides monitoring software for communication networks
* Open Systems International, an automation software vendor for the electric, petroleum, transportation and water industries
* Officine Stampaggi Industriali, a defunct Italian coachbuilder
* Ohio Scientific Inc. (also known as Ohio Scientific Instruments), a US microcomputer manufacturer 1975-1981

### Government

* Office of Scientific Intelligence, former name of a department of the Central Intelligence Agency now called the Directorate of Science and Technology
* Office of Strategic Influence, a former American government agency, part of the Department of Defense and focused on psychological warfare
* Office of Special Investigations (disambiguation), a name shared by several government agencies
** U.S. Air Force Office of Special Investigations
** Office of Special Investigations (Government Accountability Office)
** Office of Special Investigations (United States Department of Justice)
* Office of Scientific Integrity, now United States Office of Research Integrity
* Office of Special Investigation, a secret intelligence unit of Republic of Korea Air Force
* Office of the Special Investigator Australia

## Technology

* Open Systems Interconnection, (ISO 7498) a joint ISO and ITU-T standard for computer networks and communication protocols
** OSI model, a layered description for communications and computer network protocol design
** OSI protocols
* Open switching interval, a type of disconnect supervision in telecommunication
* On-Site Inspection, an advanced measure technique combining several methods, especially used in order to detect nuclear tests

## Arts and entertainment

* OSI (band), an American progressive rock supergroup named after the former Office of Strategic Influence government agency
** Office of Strategic Influence (album), the 2003 debut album by the band OSI
* Origin Systems, a former United States computer game developer
* Orchestra della Svizzera Italiana, an orchestra in southern Switzerland in the city of Lugano which is in the canton of Ticino

### Fiction

* Office of Scientific Intelligence a fictional United States government agency in several television programs and movies;
* Office of Secret Intelligence, a fictional United States government secret agency in the animated series The Venture Bros.

## People

* Osi (ancient tribe), an ancient tribe in Europe
* Alans (ancient term Osi), an ancient tribe in the Caucasus
* Osi Umenyiora (born 1981), former American football player
* Osi Rhys Osmond (1942–2015), Welsh painter

## Other uses

* Order of the Star of Italy, an order of chivalry
* Official sector involvement, in sovereign debt restructuring deals, as opposed to private sector involvement
* Options Symbology Initiative, a plan to change the way that exchange-traded options are named in option symbol
* Out-of-Station Interchange, a pedestrian change between two London Underground stations that allows continuity as part of one chargeable journey