OS

• 0S (disambiguation)
• Alexander Os
• Austrian Airlines
• Baltimore Orioles
• Coronary circulation
• Eyeglass prescription
• Leyton Orient
• List of Old Shirburnians
• List of Old Stonyhursts
• O.S. Engines
• Object sexuality
• Ocean Science (journal)
• Ohio State Buckeyes
• Ohtahara syndrome
• Old Style
• On-sight climbing
• Oneiroid syndrome
• Open source (disambiguation)
• OpenStack
• Operating system
• Oral sex
• Order of Santiago
• Order of Sikatuna
• Ordinary seaman
• Ordnance Survey
• Ordnance sergeant
• Os (Fringe)
• Os Church (disambiguation)
• Os Guinness
• Os TF
• Os du Randt
• Os, Hordaland
• Os, Innlandet
• Os, Värnamo
• Os, Østfold
• Osiedle
• Osmium
• Ossetic language
• Outlaw Star
• Overall survival rate
• Oz (disambiguation)
• Oś, Kluczbork County
• external orifice of the uterus
• internal orifice of the uterus
• per os
• ÖS (disambiguation)
• Ōs
• Ōs (rune)