| Acronym | Definition |
|---|
| OP➣Original Poster |
| OP➣Opinion |
| OP➣Operator (IRC) |
| OP➣Opus (Latin: A Work; used in referring to music) |
| OP➣Operation/Operational |
| OP➣Original Poster (internet newsgroups and message boards) |
| OP➣Other People |
| OP➣One Piece (Anime) |
| OP➣Ocean Pacific |
| OP➣Opera |
| OP➣Out of Print |
| OP➣Output |
| OP➣Office of the President |
| OP➣Opportunity (Ads) |
| OP➣Optical |
| OP➣Output (Hyper Logo command) |
| OP➣Office Professional |
| OP➣Oak Park (Illinois) |
| OP➣Opposite (volleyball position) |
| OP➣Output Power |
| OP➣Organized Play (gaming) |
| OP➣Outpost (gaming) |
| OP➣Operating Profit |
| OP➣Order of Preachers (Roman Catholicism; Dominican) |
| OP➣Overland Park (Kansas) |
| OP➣Old Patient |
| OP➣Oral Presentation |
| OP➣Outpatient |
| OP➣Osteoporosis |
| OP➣Off-Peak (time) |
| OP➣Operating Procedure(s) |
| OP➣Overpowered (gaming) |
| OP➣Opening Post (internet message boards) |
| OP➣Order Processing |
| OP➣Outreach Program |
| OP➣One Power (Wheel of Time series) |
| OP➣Olympic Peninsula (Washington) |
| OP➣Office of Policy (Social Security) |
| OP➣Optimus Prime (Leader of the Autobots, icon of the 80s) |
| OP➣Operating Pressure |
| OP➣Operator Panel |
| OP➣Oil Pulling |
| OP➣Opposing Party (legal notation and billing) |
| OP➣Observation Point |
| OP➣Organophosphate (insecticide) |
| OP➣Office Productivity (course) |
| OP➣Optical Power |
| OP➣Orifice Plate (flowmeters) |
| OP➣Order of Precedence |
| OP➣Observation Post |
| OP➣Osuuspankki (Finnish banking cooperative) |
| OP➣Operationssaal (German: Operating Room) |
| OP➣Original Production |
| OP➣Open Pollinated (botany) |
| OP➣Organophosphorus (pesticide) |
| OP➣Old Persian (linguistics) |
| OP➣Oropharynx (anatomy) |
| OP➣Osmotic Pressure |
| OP➣Operation Phoenix (San Bernadino, CA after school program) |
| OP➣Operating Plan |
| OP➣Overly Powerful |
| OP➣Oxidative Phosphorylation |
| OP➣Opportunities Page (CECOM) |
| OP➣Operational Priority (US Navy) |
| OP➣Offensive Power (online gaming) |
| OP➣Operations Order |
| OP➣Ordinis Praedicatorum (Latin: Order of Preachers) |
| OP➣Ordo Praedicatorum (Latin: Order of Preachers; formal name of Dominicans, a Catholic religious institution) |
| OP➣Orthographic Projection |
| OP➣Over Powered (gaming) |
| OP➣Operations Procedures |
| OP➣Ordnance Personnel (US Navy) |
| OP➣Oxygen Pressure |
| OP➣Outpatient Pharmacy |
| OP➣Operational Program |
| OP➣Other Procurement |
| OP➣Original Pack (pharmacology) |
| OP➣Order Point |
| OP➣Operation Officer (Navy) |
| OP➣Occiput Posterior (fetal position) |
| OP➣Oil Purifier |
| OP➣Operational Picture |
| OP➣Osteitis Pubis |
| OP➣Order of the Pelican (Society for Creative Anachronism) |
| OP➣Operation Point |
| OP➣Opponens Pollicis |
| OP➣Ouvrier Professionnel (French: Professional Worker) |
| OP➣Optional Procedure |
| OP➣Oral Production (test) |
| OP➣Occupation Permit (Hong Kong) |
| OP➣Operations Panel |
| OP➣Olden Polynice (basketball player) |
| OP➣Originating Party |
| OP➣Oligodendrocyte Progenitor |
| OP➣Over-Proof (of alcohol) |
| OP➣Operation Register |
| OP➣Opacity Project |
| OP➣Oral Participation |
| OP➣Outsource Philippines |
| OP➣Optimal Partitioning (sectorization method) |
| OP➣Orbit Prediction |
| OP➣Operator Personal |
| OP➣Operator-Promoter |
| OP➣Orbiter Payload |
| OP➣Orienteering Problem |
| OP➣Ordnance Pamphlet |
| OP➣Ohjelmointiputka (Finnish programming site) |
| OP➣Outpicked (gaming) |
| OP➣Ordnance Publication |
| OP➣Operational Phase/Project |
| OP➣Opponents Pollicis |
| OP➣Dominican Sisters of Divine Providence (religious order) |
| OP➣Overnight Per Diem |
| OP➣Overlap Pulsing |