| Acronym | Definition | External Links | |
| O |
Organization |
 |
| O2 |
Object Oriented |
|
| OA |
Office Automation |
|
| OA |
Open Access |
|
| OA |
Order Administration |
|
| OAD |
Object Activation Daemon |
|
| OADM |
Optical Add-Drop Multiplexer |
|
| OAG |
Open Applications Group |
|
| OAGEE |
Official Airlines Guide Electronic Edition |
|
| OAK |
OEM Adaptation Kit |
|
| OAL |
OEM Abstraction Layer (aka Hardware Abstraction Layer) |
|
| OAL |
OEM Adaptation Layer |
|
| OAM |
Operations, Administration and Maintenance / Operations And Management / Operations And Maintenance |
|
| OAM&P |
Operation, Administration, Maintenance, and Provisioning |
|
| OAO |
Over And Out |
|
| OAOO |
Once And Only Once |
|
| OASIS |
Organization for the Advancement of Structured Information Standards |
 |
|
|
|
| OASYS |
Office Automation SYStem |
|
| OAW |
[Microsoft] Office Activation Wizard |
|
| OAXAL |
Open Architecture for XML Authoring and Localization |
|
|
 |
|
| OBE |
Overtaken By Events |
|
| OBI |
Open Buying on the Internet (protocol) |
|
| OBR |
On Board Rotary (detection) |
|
| OBTW |
Oh, By The Way |
|
| OC |
Operator Centralization |
|
| OC |
Optical Carrier |
|
 |
|
|
| OCA |
Online Crash Analysis |
|
|
|
|
| OCC |
Other Common Carrier |
|
| OCCS |
Object Concurrency Control Service |
|
| OCD |
Out of Cell Delineation |
|
| OCE |
Other Common carrier channel Equipment |
 |
| OCF |
Object Components Framework |
|
| OCI |
Oracle Call Interface |
|
| OCILLA |
Online Copyright Infringement Liability Limitation Act |
|
|
|
|
| OCIS |
Organized Crime Information Systems |
|
| OCL |
Object Constraint Language |
|
| OCLC |
Online Computer Library Center |
|
|
|
|
| OCO |
Non-Partitioned Index |
|
| OCP |
Oracle Certified Professional |
|
| OCPS |
Open Content Publisher Standard |
|
| OCR |
Optical Character Reader / Optical Character Recognition |
|
| OCS |
On Chip Sequencer |
|
| OCSP |
Online Certificate Status Protocol |
|
| OCT |
Object Code Translator |
|
| OCU |
Office Channel Unit |
|
| OCUR |
Open Cable Unidirectional Receivers |
|
| OCX |
OLE Control eXtension |
|
| ODA |
Office Document Architecture |
|
| ODAC |
Open Document Architecture Consortium |
|
| ODAC |
Operations Distribution Administration Center |
|
| ODAC |
Oracle Data Access Components |
|
|
|
|
| ODBC |
Open DataBase Connectivity |
|
| ODCA |
Open Data Center Alliance |
|
|
|
|
| ODD |
Operator Distance Dialing |
|
| ODDD |
Operator Direct Distance Dialing |
|
| ODF |
OpenDocument Format |
|
| ODI |
Open Data-link Interface |
|
| ODM |
Object Data Manager |
|
| ODMA |
Open Document Management API |
|
| ODMG |
Object Data Management Group |
|
|
|
|
| ODP |
Open Directory Project |
|
|
|
|
| ODRAM |
Optical Dynamic Random Access Memory |
|
| ODS |
Open Data Services |
|
| ODS |
Operational Data Store |
|
| ODS |
Optical Data Systems |
|
| ODS |
Overhead Data Stream |
|
| ODT |
Operator Display Terminal |
|
| OECD |
Organization for Economic Cooperation and Development |
|
| OED |
Oxford English Dictionary |
|
|
|
|
| OEM |
Original Equipment Manufacturer |
|
| OEMF |
Open Element Management Framework |
|
| OF |
Overflow |
|
| OFB |
(K-bit) Output Feedback |
|
| OFC |
Open Financial Connectivity (specification) |
|
| OFDM |
Orthogonal Frequency Division Multiplexing |
|
| OFE |
Open Forum Europe |
|
|
|
|
| OFLC |
Office of Film and Literature Classification |
|
|
|
|
| OFNPS |
Outstate Facility Network Planning System |
|
| OFP |
Open FORTRAN Parser |
|
|
|
|
| OFX |
Open Financial Exchange |
|
| OG |
Open Graph (protocol) |
|
|
|
|
| OGDL |
Ordered Graph Data Language |
|
|
|
|
| OGP |
Open Graph Protocol |
|
|
|
|
| OGT |
OutGoing Trunk |
|
| OGVT |
OutGoing Verification Trunk |
|
| OH |
(modem) Off Hook |
|
| OHCI |
Open Host Controller Interface |
|
|
|
|
| OHP |
OverHead Projection (film) |
|
| OI |
Object Inherit |
|
| OIAM |
One In A Million |
|
| OIAP |
Object Independent Authorization Protocol |
|
| OIC |
Oh, I See |
|
| OID |
Object Identifier |
|
| OIDL |
Object Interface Definition Language |
|
| OIL |
Ontology Inference Layer |
|
| OIM |
Open Information Model |
|
| OIN |
Open Invention Network |
|
|
|
|
| OISC |
One Instruction Set Computer |
|
|
|
|
| OISF |
Open Information Security Foundation |
|
|
|
|
| OJT |
On the Job Training |
|
| OLAP |
On-Line Analytical Processing |
|
| OLE |
Object Linking and Embedding |
|
| OLED |
Organic Light Emitting Diode |
|
| OLI |
Originating Line Information |
|
| OLM |
OnLine Mafia |
|
| OLTM |
Optical Line Terminating Multiplexer |
|
| O-LTM |
Optical Line Terminating Multiplexer |
|
| OLTP |
On-Line Transaction Processing |
|
| OLTS |
OnLine Test System |
|
| OLX |
Off-Line eXpress |
|
| OMA |
Open Mashup Alliance |
|
|
|
|
| OMB |
[U.S.] Office of Management and Budget |
|
|
|
|
| OMDOC |
Open Mathematical Documents |
|
| OMF |
Object Module Format |
|
| OMFI |
Open Media Framework Interchange |
|
| OMG |
Object Management Group (model) |
|
| OMG |
Oh My God |
|
| OML |
Open Modeling Language |
|
| OMM |
Output Message Manual |
|
| OMPF |
Operation and Maintenance Processor Frame |
|
| OMR |
Optical Mark Recognition (technology) |
|
| OMT |
Object Modeling Technique |
|
| ONA |
Open Network Architecture |
|
| ONAC |
Operations Network Administration Center |
|
| ONAL |
Off Network Access Line |
|
| ONE |
[Sun] Open Net Environment |
|
|
|
|
| ONF |
Open Networking Foundation |
|
|
|
|
| ONFI |
Open NAND Flash Interface (sometimes as ONFi) |
|
|
|
|
| ONI |
Operator Number Identification |
|
| ONNA |
Oh No, Not Again |
|
| ONNTA |
Oh No, Not This Again |
|
| ONS |
Object Naming Service |
|
| ONT |
Optical Network Terminal |
|
|
|
|
| ONU |
Optical Network Unit |
|
|
|
|
| ONVIF |
Open Network Video Industry Forum |
|
|
|
|
| OO |
Object Oriented |
|
| OOA |
Object Oriented Analysis |
|
| OOA |
Out-Of-Area |
|
| OOB |
Out Of Band |
|
| OOBE |
Out-Of-Box Experience |
|
| OOD |
Object Oriented Design |
|
| OODB |
Object Oriented DataBase |
|
| OODCE |
Object Oriented Distributed Computing Environment |
|
| OOF |
Out Of Frame |
|
| OOI |
Out Of Interest |
|
| OOP |
Object Oriented Programming |
|
| OOPSLA |
Object Oriented Programming Systems, Language and Applications |
|
| OOT |
Object Oriented Technology |
|
| OOTB |
Out Of The Blue |
|
| OOTB |
Out Of The Box (meaning brand new) |
|
| OOTC |
Obligatory On Topic Comment |
|
| OOUI |
Object Oriented User Interface |
|
| OOV |
Order of Volatility |
|
| OOXML |
Office Open eXtensible Markup Language |
|
|
|
|
| OP |
Outside Plant |
|
| OPA |
Oracle Protocol Adapter |
|
| OPAC |
Online Public Access Catalogues |
|
| OPAL |
On-line Presentation Access Library |
|
| OPC |
Open Packaging Convensions |
|
| OPC |
Originating Point Codes |
|
| OPCR |
Original Program Clock Reference |
|
| OPEN |
Open Protocol Enhanced Networks |
|
| OPEOS |
Outside Plant planning, Engineering & construction Operations System |
|
| OPI |
Open Prepress Interface |
|
| OPI |
Oracle Program Interface |
|
| OPIE |
Open Palmtop Integrated Environment |
|
|
|
|
| OPK |
Open Product Key |
|
| OPLA |
On-screen Product License Agreement |
|
| OPM |
[U.S.] Office of Personnel Management |
|
|
|
|
| OPM |
Other People's Money |
|
| OPM |
Outage Performance Monitoring |
|
| OPM |
Output Protection Management |
|
| OPM |
Outside Plant Module |
|
| OPOS |
OLE for Point Of Sale |
|
| OPP |
(Bluetooth) Object Push Profile |
|
| OPP |
Optional Program Products |
|
| OPS |
Off Premises Station |
|
| OPS |
Open Profiling Standard |
|
| OPS |
Operations |
|
| OPS |
Oracle Parallel Server |
|
| OPSM |
Outside Plant Subscriber Module |
|
| OPT |
Open Protocol Technology |
|
| OPX |
Off Premises eXtension |
|
| OR |
Onward Routing |
|
|
|
|
| OR |
Originating Register |
|
| ORB |
Object Request Broker |
|
| ORB |
Office Repeater Bay |
|
| ORDB |
Open Relay DataBase |
|
|
|
|
| ORG |
Organization (usually as .org) |
|
| ORM |
Object-Relational Mapping (sometimes as O/RM) |
|
| ORM |
Optical Remote Module |
|
| ORSD |
Object Registration Service Daemon (usually as orsd) |
|
| OS |
Operating System |
|
| OS |
Operator Service |
|
| OS |
Output Spy (ITS) |
|
| OS |
OutState |
|
| OS/2 |
Operating System/2 |
|
|
|
|
| OSA |
Optical Society of America |
|
|
|
|
| OSAC |
Operator Services Assistance Center |
|
| OSAP |
Object Specific Authorization Protocol |
|
| OSC |
Operator Services Center |
|
| OSC |
OSCillator |
|
| OSCA |
Open Systems Color Association |
|
| OSCAR |
Open Standards for Container/content Allowing Reuse |
|
|
|
|
| OSCOM |
Open-Source Content Management |
|
| OSD |
[U.S.] Office of the Secretary of Defense |
|
|
|
|
| OSD |
Object-based Storage Device |
|
| OSD |
Open Software Description |
|
| OSDS |
Operating System for Distributed Switching |
|
| OSE |
Open Systems Environment |
|
| OSE |
Operating System Environment |
|
| OSF |
Open Software Foundation |
|
|
|
|
| OSF |
Operations System Function |
|
| OSF/DCE |
Open Software Foundation Distributed Computing Environment |
|
|
|
|
| OSG |
Open Services Gateway (standard) |
|
| OSGI |
Open Services Gateway initiative (usually as OSGi) |
|
| OSHA |
[U.S.] Occupational Safety and Health Administration |
|
|
|
|
| OSI |
Open Source Initiative |
|
|
|
|
| OSI |
Open Systems Interconnect / Open Systems Interconnection (model) |
|
| OSI/CS |
Open Systems Interconnection / Communications Subsystem |
|
| OSID |
Originating Signaling Identifier |
|
| OSIE |
Open Systems Interconnection Environment |
|
| OSINET |
Open Systems Interconnection NETwork |
|
| OSIRM |
Open Systems Interconnection Reference Model |
|
| OSME |
Open Systems Message Exchange |
|
| OSO |
Originating Signaling Office |
|
| OSP |
Online Service Provider |
|
|
|
|
| OSP |
OutSide Plant |
|
| OSPF |
Open Shortest Path First (protocol) |
|
| OSPS |
Operator Service Position System |
|
| OSR |
OEM Service Release |
|
| OSRM |
Open Source Risk Management |
|
| OSS |
Open Source Software |
|
| OSS |
Operational Support System |
|
| OSS |
Operations Support Services |
|
| OSS |
Operator Service System |
|
| OSSWG |
Office System Standards Work Group |
|
| OSTA |
Optical Storage Technology Association |
|
|
|
|
| OSTC |
Open Systems Testing Consortium |
|
| OSTP |
Office of Science and Technology Policy |
|
| OSWD |
Open Source Web Design |
|
|
|
|
| OSWS |
Operating System WorkStation |
|
| OT |
Object Technology |
|
| OT |
Off Topic |
|
| OTA |
(Congressional) Office of Technology Assessment |
|
|
|
|
| OTA |
Over The Air |
|
| OTC |
Operating Telephone Company |
|
| OTC |
Over-The-Counter |
|
|
|
|
| OTDR |
Optical Time Domain Reflectometer |
|
| OTE |
Off Track Excursion / Off Track Experience |
|
| OTF |
Object Testing Framework |
|
| OTF |
On The Floor |
|
| OTG |
On-The-Go |
|
| O-T-G |
On-The-Go |
|
| OTL |
OSI Testing Liaison |
|
| OTOH |
On The Other Hand |
|
| OTOOH |
On The Other Other Hand |
|
| OTP |
On The Phone |
|
| OTP |
One Time Password |
|
| OTP |
One Time Programmable |
|
| OTP |
Order Transaction Processing |
|
| OTQ |
Out-going Trunk Queuing |
|
| OTS |
Object Transaction Service |
|
| OTS |
Off The Shelf |
|
| OTT |
Off The Topic |
|
| OTT |
Over The Top |
|
| OTTH |
On The Third Hand |
|
| OTTOMH |
Off The Top Of My Head |
|
| OU |
Organizational Unit |
|
| OUI |
Organizationally Unique Identifier |
|
|
|
|
| OURS |
Open User Recommended Solutions (user group) |
|
| OUTWATS |
OUTward Wide Area Telecommunications Service |
|
| OV |
[HP] OpenView |
|
|
|
|
| OVD |
Optical Video Disk |
|
| OVDA |
Optical Video Disc Association |
|
| OVF |
Open Virtualization Format |
|
| OW |
Over - Write |
|
| OWASP |
Open Web Application Security Project |
|
| OWF |
One-Way Function |
|
| OWF |
Optimum Working Frequency |
|
| OWL |
Object Windows Library |
|
| OWN |
Oprah Winfrey Network |
|
|
|
|
| OWRTS |
Open - Wire Radio Transmission System |
|
| OWTL |
Open - Wire Transmission Line |
|
