| Acronym | Definition |
|---|
| RFU | Rugby Football Union |
| RFU | Remote Firmware Update (firmware) |
| RFU | Relative Fluorescence Units |
| RFU | Reserved For Future Use |
| RFU | Russian Football Union |
| RFU | Radio Frequency Unit |
| RFU | Ready For Use |
| RFU | Reach for Unbleached (Canada; est. 1991) |
| RFU | Radical Fundamentalist Unit (US FBI) |
| RFU | Remote Fan Unit |
| RFU | Reconfigurable Functional Unit |
| RFU | Réserve Facilement Utilisable (French: Readily Available Reserve) |
| RFU | Request for Update |
| RFU | Remote Focusing Unit (to focus robotic lighting instruments on stage) |
| RFU | Reason for Update (electronic document processing) |
| RFU | Rolling Foul-Up |
| RFU | Sub-Capacity Dispersion Range (US FBI) |