Osa or OSA may refer to:
Places Osa Peninsula, in Costa Rica Osa (canton), in the province of Puntarenas in Costa Rica Osa Conservation Area, an administrative area in Costa Rica Osa, India, a village in Allahabad, India Osa, Iran, a village in Mazandaran Province, Iran Osa, Warmian-Masurian Voivodeship, north Poland Osa, a minor tributary of the Vistula, Poland Osa, Norway, a village in Ulvik municipality, Vestland county, Norway Osa, Russia, the name of several inhabited localities in Russia Osa, Missouri, a community in the United States
Military Osa-class missile boat 9K33 Osa (SA-8 Gecko), a Soviet surface-to-air missile launcher M79 Osa, a Serbian/Yugoslav rocket launcher Avia B.122 Osa, a Czech trainer aircraft Osa (handgun) a Russian non-lethal handgun Osa (drone), Ukrainian uncrewed aerial vehicle (UAV)
Schools Oakland School for the Arts Old Scona Academic High School, a school in Edmonton, Canada
Science and technology Optical spectrum analyzer Osa (plant), a monotypic genus of plant in the family Rubiaceae
Medicine Obstructive sleep apnea, a sleep-related breathing disorder in which upper airway obstruction leads to reduced breathing that interrupts normal sleep Osteosarcoma, a malignant neoplasm of bone
Computing Open Scripting Architecture, for AppleScript Open Services Access, a set of standards for mobile telecommunications Online Sexual Activity Open Systems Adapter, an IBM card for mainframes Open systems architecture, a telecommunication standard
Businesses and organizations Oceania Swimming Association Ontario Soccer Association Ontario Society of Artists Open Solutions Alliance Optical Society of America, now Optica Optimization Systems Associates, a defunct American software company Order of Saint Anna, a Russian order of chivalry Order of Saint Augustine (Ordo Sancti Augustini), the Roman Catholic Augustinian order Oregon Student Association Organization of the Secret Army, French far-right nationalist group in Algeria OSA, a Czech Republic performance rights organisation Oriental Society of Australia, now the Australian Society for Asian Humanities OSA Group, a Constructivist architectural association of the 1920s based in the USSR The Odisha Society of the Americas Intelligence-Security Agency of Bosnia and Herzegovina (Obavještajno sigurnosna / bezbjednosna agencija, or OSA-OBA), an intelligence and security agency of Bosnia and Herzegovina Office of the Science Advisor, of the United States Environmental Protection Agency Office of Special Affairs, a controversial department of the Church of Scientology Operation Save America
People Sumire Haruno, Japanese actress, nicknamed Osa Osa Johnson (1894-1953), American filmmaker Osa Maliki (1907–1969), Indonesian politician Osa Massen (1914–2006), Danish actress Osa Odighizuwa (born 1998), American football player Lars Osa (1860–1958), Norwegian artist
Other uses Old Stone Age or Paleolithic Office of Secret Actions, a fictional government department in the video game Return to Castle Wolfenstein Official Secrets Act, legislation in several countries Online Safety Act (disambiguation), legislation in various countries (including Australia, Sri Lanka, United Kingdom, and United States) Online savings account Open skies agreement Osaka International Airport (former IATA code: OSA)
See also Ossa (disambiguation)