| Abbreviation | Definition |
|---|---|
| OPL | Obvious Panty Line |
| OQA | Oxford Quilt-lined Award Jacket |
| OQY | Oxford Quilt-lined award Youth Jacket |
| OS | One Size |
| OS | Over Sized |
| OSFA | One Size Fits All |
| OSFM | One Size Fits Most |
| OTP | One True Pair |
| OU | Oregon Unitards |
| OVV | Orange Vinyl Vest |
| OWAO | Old West Anglers and Outfitters |
| P | Pajama |
| PASG | Pneumatic Anti-Shock Garment |
| PB | Partial body |
| PB | PlackettBurman |
| PB | Plackett–Burman |
| PBB | Perfectly Balanced Buttonholes |
| PBS | Pink Bunny Slippers |
| PC | Pearl Cotton |
| PCH | Premium Cotton Heater |