| Abbreviation | Definition |
|---|---|
| FTO | Foreign Terrorist Organization |
| FUBAR | Fouled Up Beyond All Recognition |
| FUDE | FUgitive/DEserter |
| GDS | General Declassification Schedule |
| GEMS | Global Energy Management Solutions |
| GID | General Intelligence Division |
| GIIF | General Investigative Intelligence File |
| GIM | Generic Information Model |
| GJ | Grand Jury |
| GK | Great Killers |
| G-Men | Government Agents |
| GOON | Guardian Of the Oglala Nation |
| HCUA | House Committee on Un-American Activities |
| HISC | House Internal Security Committee |
| HLC | High Level Contact |
| HN | Honolulu Field Office |
| HO | Houston Field Office |
| I | Identical |
| I | Integrity |
| IA | Informative Asset |