| Abbreviation | Definition |
|---|---|
| HCSW | Hypersonic Conventional Strike Weapon |
| HCT | HUMINT (HUMan INTelligence) Collection Team |
| HCTA | Helicopter Composite Technology Application |
| HCTB | High Casualty Terrorist Bombings |
| HCTR | High Capacity Truck Radio |
| HCU | High-Capacity Computer Unit |
| HD | A Mustard Agent |
| HD | Hardware Design |
| HD | Harmonic Distortion |
| HD | Home Defense |
| HD | Homeland Defense |
| HD | Hull Defilade |
| HD | Mustard gas, Distilled (military designation) |
| HDAS | Heavy- Duty Auxiliary Stand |
| HDBK | Handbook |
| HDC | Harbor Defense Commander |
| HDC | Helicopter Direction Center |
| HDCU | Harbor Defense Command Unit |
| HDD | Hard Disk Drive |
| HDD | Hardware Design Document |