| Abbreviation | Definition |
|---|---|
| PTN | Palatin Technologies, Inc |
| PW | Pittsburgh & West Virginia Railroad |
| PWX | Providence & Worcester Railroad Company |
| PYR | PYR Energy Corporation |
| PZA | Provena Foods, Inc. |
| Q | Quantitative |
| QLY | Quality Leisure in York |
| QMQ | Immucor, Inc. options |
| QPJ | United Surgical Partners International options |
| QQQ | NASDAQ 100 Index Tracking stock |
| QSC | Questcor Pharmaceuticals, Inc. |
| QTK | Quiktrak Networks Limited |
| RAC | Rampart Capital Corporation |
| RAS | Resource Asset Investment Trust |
| RBC | Regal Beloit Corporation |
| RBV | Resources Bankshares Corporation |
| RCF | Rica Foods, Inc. |
| RCO | Ramco Energy, PLC |
| RCP | Morgan Stanley Dean Witter |
| RDIA | Reading International, Inc. Class A |