- OCSG
- Open Canoe Sailing Group (Miscellaneous » Hobbies)*** Open Computing Security Group (Computing » Security)*** Open Computing Security Group (Computing » General)*** Operating Capability Study Group (Governmental » Military)** Orchestre des Concerts Symphoniques de Gatineau (Community » Music)** Ohio Council Of Student Governments (Community » Educational)* Ohio Cost Savings Group (Business » Firms)* Open Canoes Sailing Group (Community » Sports)* Operation Capacity Study Group (Medical » Hospitals)* Organized Crime Strategy Group (Governmental » Police)
Abbreviations dictionary. 2012.