| Acronym | Definition |
|---|
| OC | Optical Carrier |
| OC | Orange County (California; New York) |
| OC | Over Clock (computer CPU) |
| OC | Of Course |
| OC | Orange County (TV show) |
| OC | Oklahoma Christian University |
| OC | Ocean City, MD |
| OC | Ocean City |
| OC | Open Carry (firearm possession) |
| OC | Original Character (fanfiction new, made-up character) |
| OC | OxyContin (prescription drug; aka Oxys) |
| OC | Out of Control |
| OC | Odessa College (Odessa, Texas) |
| OC | Open Circuit (SCUBA and electronics) |
| OC | On Center |
| OC | Online Community |
| OC | Original Content |
| OC | Organic Carbon |
| OC | On Camera |
| OC | Obsessive-Compulsive |
| OC | Oral Contraceptive |
| OC | Off Camera (cinematography) |
| OC | Organized Crime |
| OC | Oleoresin Capsicum (active ingredient in pepper spray) |
| OC | Oregon City (Oregon) |
| OC | Oberlin College (Oberlin, Ohio) |
| OC | Overcoat |
| OC | Oregon Coast |
| OC | On Course |
| OC | Order of Canada |
| OC | Oak Cliff (Dallas neighborhood) |
| OC | Oliver Cromwell |
| OC | Oral Communication |
| OC | Other Character |
| OC | Officer Commanding |
| OC | Operating Cost |
| OC | Oversight Committee |
| OC | Office of Communications |
| OC | Overcurrent |
| OC | Operating Company |
| OC | Optical Communications |
| OC | Officer in Command |
| OC | Old Chinese (language of pre 400BC) |
| OC | OpenCup (online tournament) |
| OC | Organochlorine |
| OC | Object Class |
| OC | Open Collector (electronics, transistors) |
| OC | Office of Compliance (US FDA) |
| OC | Officer of the Order of Canada |
| OC | Old Chap (ham radio shorthand) |
| OC | Ottawa-Carleton |
| OC | Optical Channel |
| OC | Operational Control |
| OC | Open Content |
| OC | Operating Characteristic |
| OC | Office of the Commissioner |
| OC | Open Canvas (art program) |
| OC | Office of the Comptroller |
| OC | Oakland City (Indiana College) |
| OC | Operational Capability |
| OC | Operation Center |
| OC | Officer Candidate |
| OC | Operator Console |
| OC | Old Covenant (biblical law) |
| OC | Operant Conditioning (a training technique) |
| OC | Opposing Counsel (legal notation) |
| OC | Outside Corner (measuring in construction) |
| OC | Operating Committee |
| OC | Ondes Courtes (French: shortwave) |
| OC | Orlando Cabrera (baseball player) |
| OC | Obstetric Cholestasis |
| OC | Oxnard College (Oxnard, CA) |
| OC | Over Crowded |
| OC | Output Compare |
| OC | Observer Controller |
| OC | Open Computing |
| OC | Oceanic Crust |
| OC | Operation Class |
| OC | Output Coupler (optics, lasers) |
| OC | Ocean Conservancy |
| OC | Operations Coordinator |
| OC | Offering Circular |
| OC | Oracle Clinical |
| OC | Oakwood College (Alabama) |
| OC | Oglethorpe County (Georgia) |
| OC | Optical Colonoscopy |
| OC | On-scene Commander |
| OC | Operations Controller |
| OC | Overture Center (performing arts) |
| OC | Output Check |
| OC | Out Calls |
| OC | Organisme Certificateur |
| OC | Out Cast (gaming clan) |
| OC | One Communications, Inc. |
| OC | Occupancy Certificate (residential license) |
| OC | Christian O'Connell (radio personality; UK) |
| OC | Octopus Card (Hong Kong smart payment card) |
| OC | Operating Curve |
| OC | Organisme Conventionné (French: Accredited Body) |
| OC | Operation Channel |
| OC | Outdoors Center (Texas A&M) |
| OC | Outside Circumference |
| OC | Over-Crossing |
| OC | Ordinary Cadet |
| OC | Orientation Counselor |
| OC | Operation Context |
| OC | Oxygen Cutting |
| OC | Opere Citato (Latin: In the Work Cited) |
| OC | Operator Centralization |
| OC | Organizational Committee of ACC |
| OC | Odin's Court (rock and metal band) |
| OC | Ormiston College |
| OC | Ordres Courants (French: current orders) |
| OC | Oudste Categorie (Dutch) |
| OC | Officer's Cook |
| OC | Organizadora de Comercio (Spanish; Guatemala) |
| OC | Otaku Convention (Japanese film festival) |
| OC | Ordnance Controller |
| OC | Office and Communication Module |
| OC | Outside Contracting/Contractor |
| OC | Order of the Carmelites (religious order) |
| OC | Outage Continuing |
| OC | Outer Chuck |
| OC | Operational Concept/Operating Concept |
| OC | Open Within Memory Cell |
| OC | Office Coordinator (administrative position) |
| OC | Omnipotent Carnage (gaming clan) |
| OC | Owl City (band) |
| OC | Orange Crush |