| Abbreviation | Definition |
|---|---|
| TEPCI | Top Echelon Potential Criminal Informant |
| TFIS | Theft From Interstate Shipment |
| TGP | Theft of Government Property |
| TIC | TICkler dopy of document |
| TIO | Time In Office |
| TISA | Test, Inhibit, Squelch, Act |
| TIT | Terrorist In Training |
| TOPCI | Time on Potential Criminal Informants |
| TOPLEV | TOP LEVel |
| TOPRI | Time on Potential Racial Informants |
| TOPSI | Time on Potential Security Informants |
| TP | Tampa Field Office |
| TSCM | Technical Surveillance Counter-Measures |
| TTS | Terrorist Training School |
| U | Unavailable |
| UACB | Unless Advised to Contrary by the Bureau |
| UCR | Uniform Crime Reports |
| UFAC | Unlawful Flight to Avoid Confinement |
| UFAP | Unlawful Flight to Avoid Prosecution |
| UFO | Unlicensed Female Operative |