| ORB | O Ring Base 
| Others |
| ORB | O Ring Boss
| Others |
| ORB | Oak Ridge Boys
| Others |
| ORB | Object Relation Builder
| Others |
| ORB | Object Request Broker
| Others |
| ORB | Object Ring Buffer
| Others |
| ORB | Objective Remote Bandwidth
| Others |
| ORB | Observatoire Royal de Belgique (Royal Observatory of Belgium)
| Others |
| ORB | Obviously Really Bad
| Others |
| ORB | Of Remarkable Beauty
| Others |
| ORB | Off Road Base
| Others |
| ORB | Off Road Beast
| Others |
| ORB | Off Road Buggy
| Others |
| ORB | Office Repeater Bay
| Others |
| ORB | Officer Record Brief
| Others |
| ORB | Offworld Resource Base
| Others |
| ORB | Oil Record Book
| Others |
| ORB | Oil Rubbed Bronze
| Others |
| ORB | One Reply B*tch
| Others |
| ORB | Online Radio Box
| Others |
| ORB | Online Record Book
| Others |
| ORB | Online Reference Book
| Others |
| ORB | Online Remote Base
| Others |
| ORB | Online Reporting Button
| Others |
| ORB | Online Resource Bank
| Others |
| ORB | Ontario Review Board
| Others |
| ORB | Ontology Referential Base
| Others |
| ORB | Open Repository Binghamton
| Others |
| ORB | Opening range breakout
| Others |
| ORB | Operating Resident Browser
| Others |
| ORB | Operation Reconstructive Baby
| Others |
| ORB | Operational Relay Box
| Others |
| ORB | Operational Review Board
| Others |
| ORB | Operations Record Book
| Others |
| ORB | Opinion Really Boring
| Others |
| ORB | Opinion Research Business
| Others |
| ORB | ORBit
| Others |
| ORB | Orbital Ring Bluetooth
| Others |
| ORB | Orebro, Sweden
| Others |
| ORB | Organic Radical Battery
| Others |
| ORB | Otto Robert Bade
| Others |
| ORB | Outreach Red Bank
| Others |