English abbreviations from ocs to ocy
- OCS (Officer Candidate School, located at Naval Station Newport)
- OCSA (Office of the Chief of Staff, Army)
- OCSC (Orange Council of Ski Clubs)
- OCSG (Ohio Council Of Student Governments)
- OCSH (Ohio Coalition for Safe Highways)
- OCSHA (Off-Campus Student Housing Association)
- OCSI (Open Collaboration Services Initiative)
- OCSLA (Outer Continental Shelf Lands Act (oil))
- OCSN (Official College Sports Network)
- OCSP (Online Certificate Status Protocol)
- OCSW (Objective Crew-Served Weapon)
- Oct. (Octava ("Octave" Breviary))
- OCT (Oklahoma City Thunder)
- OCTG (Oil Country Tubular Goods (oil well casing, tubing, and drill pipe)Oil Country Tubular Goods (oil well casing, tubing, and drill pipe))
- OCTR (Orange County Trail Runners)
- OCU (Operational Centre Unit)
- OCU-1 (Orderwire Control Unit-1)
- OCUA (Ottawa Carleton Ultimate Association)
- OCUC (Owatonna College University Center)
- OCV (Open Circuit Voltage)
- OCW (Warren Field)
- OCX (OLE Control Extension)
- OCY (Oakland County Youth)