OAS
# OAS

OAS or Oas may refer to:

## Chemistry

* O-Acetylserine, amino-acid involved in cysteine synthesis

## Computers

* Open-Architecture-System, the main user interface of Wersi musical keyboards
* OpenAPI Specification (originally Swagger Specification), specification for machine-readable interface files for RESTful Web services
* Oracle Application Server, software platform

## Medicine

* Open aortic surgery, surgical technique
* Oral allergy syndrome, food-related allergic reaction in the mouth
* 2'-5'-oligoadenylate synthase, an enzyme
   * OAS1, OAS2, OAS3, anti-viral enzymes in humans

## Organizations

* Office of Aviation Services, agency of the United States Department of the Interior
* Ontario Archaeological Society, organization promoting archaeology within the Province of Ontario, Canada
* Organisation Armée Secrète, French dissident terrorist organisation, active during the Algerian War (1954–62), fighting against Algerian independence
* Organization of American States, continental organization of the Western Hemisphere
* Oxford Art Society, society for artists in the city of Oxford, England

## Transport

* Oasis LRT station, Singapore, LRT station abbreviation OAS

## Other

* Ohio Auction School, school for auctioneers in Ohio, U.S.
* Old Age Security, social security payment available to most Canadians aged 65 or older
* Option-adjusted spread, the yield-curve spread of a fixed-income security, adjusted for the cost of embedded options
* Oas, Albay, municipality in the Philippines
