| Abbreviation | Definition |
|---|---|
| FINL | Flame/Incendiary and Non-Lethal |
| FINS | Freight Information System |
| FIO | Force Integration Office |
| FIOP | Family of Interoperable Operational Pictures |
| FIPS | Federal Information Processing Standards |
| FIR | Field Inspection Manual |
| FIR | Final Inspection Report |
| FIR | First-Impressions Report |
| FIRCAP | Foreign Intelligence Requirements Capabilities and Priorities |
| FIREFLEX | Flexible Fire Support System |
| FIREX | Fire Exercise |
| FIRM | Fresno Interdenominational Refugee Ministries |
| FIROPS | Freedom of Air Operations |
| FIRS | FORSCOM Issue Resolution System |
| FIRST | Fast Israeli Rescue and Search Team |
| FIRST | Forum of Incident Response and Security Teams |
| FIRTI | ar Infrared Target Indicators |
| FIRTI | Far Infrared Target Indicators |
| FIS | Flight Information Service |
| FIS | Foreign Intelligence Service |