| Abbreviation | Definition |
|---|---|
| HAIPE | High Assurance Internet Protocol Encryptor |
| HAIR | Hardcore Alternative Indie Rap |
| HAJ | Holy American Jihad |
| HALE | High Altitude Long Endurance |
| HALO | High Altitude Low Open |
| HALO | High Altitude Low Opening |
| HALO | High Altitude Observatory |
| HALO | High-Altitude Low-Opening Parachute Technique |
| HALO | Hypersonic Air-Launched Offensive |
| HALS | Helicopter Automatic Landing System |
| HAM | Amateur Radio Operator |
| H-AMI | Host Automated Message Interface |
| HANE | High Altitude Nuclear Explosion |
| HAP | High Altitude Prototype |
| HAP | Humanitarian Assistance Program |
| HAP-EP | Humanitarian Assistance Program-Excess Property |
| HAPL | High Average Power Lasers |
| HARD | Helmet Assisted Radar Detection |
| HARM | Heavy Anti Radiation Missile |
| HARM | High-Speed Antiradiation Missile |