Editing OS

{{For|usage on Wikipedia|Wikipedia:Oversight|selfref=yes}}
{{wiktionary|OS|Os|os}}
'''OS''', '''O.S.''', '''Os''', '''O's''', or '''os''' may refer to:
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== Computing ==
* [[Operating system]], computer system software that manages the hardware and software of a computer
* [[Open source (disambiguation)]]
* [[OpenStack]], a software platform for cloud computing

== Medicine ==
* os, a [[bone]] in [[French language|french]]
* os or ostium, a [[mouth]] or mouth-like opening
** ''external os'', the [[external orifice of the uterus]]
** ''internal os'', the [[internal orifice of the uterus]]
** ''[[per os]]'', meaning "ingestion by mouth"
** ''os'' or ''ostium'', the opening of a [[Coronary circulation|coronary artery]]
* ''O.S.'' or ''OS'', ''oculus sinister'', meaning "left eye" in general ophthalmologic or optometric usage, particularly  in [[Eyeglass prescription#Abbreviations and terms|eyeglass prescriptions]] (deprecated abbreviation)
* [[Ohtahara syndrome]], a brain disorder
* [[Overall survival rate]], a cancer survival statistic
* [[Oneiroid syndrome]], a dreamlike fantastic delusional state

== People ==
* [[Alexander Os]] (born 1980), a Norwegian biathlete
* [[Os du Randt]] (born 1972), a South African rugby player
* [[Os Guinness]] (born 1941), an English author and social critic

== Places ==
=== Norway ===
* [[Os, Innlandet]], a municipality in Innlandet county, Norway
* [[Os, Hordaland]], a former municipality in Hordaland county, Norway
* [[Os, Østfold]], a parish in Rakkestad municipality in Østfold county, Norway
* [[Os Church (disambiguation)|Os Church]], a name for several churches in Norway

=== Poland ===
* [[Oś, Kluczbork County]], a village in Kluczbork County, Opole Voivodeship, Poland
* [[Osiedle]] (Os.), a Polish term used for housing subdivisions in Poland

=== Germany ===
* [[Opavian Silesia]], a historical subregion of Silesia (Upper Silesia) in the Czech Republic

=== Other places ===
* [[Os, Värnamo]], a village in Värnamo Municipality, Småland province, Sweden
* OS, [[List of airports by ICAO code: O#OS - Syria|ICAO code]] for airports in Syria
* OS, WMO country code for [[Austria]]

== Religion ==
* [[Ōs]], an Old English word denoting a god in Anglo-Saxon paganism, related to ''æsir''
* O.S., [[Order of Santiago]], a Spanish order dedicated to St James the Greater
* O.S., [[Order of Sikatuna]], the national order of diplomatic merit of the Philippines

== Science ==
* [[Ocean Science (journal)|''Ocean Science'' (journal)]], an oceanographic journal
* [[Osmium]], symbol Os, a chemical element

== Businesses ==
* [[Ordnance Survey]], national mapping agency of Great Britain
* [[Austrian Airlines]] (IATA code OS based on its original name: ''Österreichische Luftverkehrs AG'')
* [[O.S. Engines]], a Japanese manufacturer of model aircraft engines

== Entertainment ==
* [[Os (Fringe)|"Os" (''Fringe'')]], an episode of the television show ''Fringe''
* ''[[Outlaw Star]]'', a manga and anime series
* [[Prompt corner]], OS, opposite prompt or stage right in a theatre

== Sport ==
* [[Ohio State Buckeyes]], a group of collegiate teams representing The Ohio State University
* [[Os TF]], a sports club in Os, Norway
* [[On-sight climbing]], an ascent of a rock climbing route on the first attempt
* [[Baltimore Orioles]], an American baseball team nicknamed "O's"
* [[Leyton Orient]], an English football (soccer) team nicknamed "O's"

== Titles ==
* [[Ordinary seaman]], an unlicensed member of the deck department of a merchant ship
* [[Ordnance sergeant]], an enlisted rank in the U.S. and Confederate armies during the American Civil War era
* Old Shirburnian, used by [[List of Old Shirburnians|alumni of Sherborne School]]
* Old Stonyhurst, used by [[List of Old Stonyhursts|alumni of Stonyhurst College]]

== Other uses ==
* [[Esker]], also os, a long, winding ridge of sand and gravel in (formerly) glaciated regions
* [[Ōs (rune)]] (ᚩ), a rune of the Anglo-Saxon fuþorc
* [[Old Style and New Style dates|Old Style]] (O.S.) date, indicating use of an earlier calendar (in Anglophone countries, the Julian Calendar), as opposed to "N.S." (new style), usually indicating use of the Gregorian Calendar
* [[Ossetic language]] (ISO 639-1 abbreviation OS)
* [[Object sexuality]], sexual attraction to inanimate objects
* [[Oral sex]]

== See also ==
* [[0S (disambiguation)]]
* [[ÖS (disambiguation)]]
* [[Oz (disambiguation)]]

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