| Abbreviation | Definition |
|---|---|
| OSC | Order of Scottish Clans |
| OTG | Old Timers Guild |
| OWMG | Operative Web Masons Guild |
| PAAG | Pottstown Area Artists Guild |
| PBG | Premier Builders Guild |
| PCG | Piedmont Culinary Guild |
| PCTG | Portland Civic Theatre Guild |
| PDG | Princeton Design Guild |
| PETA | Pedophiles Entice The Adults |
| PFGA | Picture framers guild of Australia |
| PFN | Past Faithful Navigator |
| PGA | Producers Guild of America |
| PGI | Platinum Guild |
| PGI | Platinum Guild International |
| PGI | Pyrotechnics Guild International |
| PGK | Past Grand Knight |
| PLG | Progressive Librarians Guild |
| PMOG | Philippine Marine Officers Guild |
| PNG | professional numismatist guild |
| PPG | Pet Professional Guild |