| Acronym | Definition |
|---|
| HFFI➣Healthy Fast Food, Inc. (est. 2005; Henderson, NV) |
| HFFI➣Historic Fredericksburg Foundation, Inc. (Virginia) |
| HFFI➣High Frequency Flow Interruption |
| HFFI➣Heavy Fuel Flow Improver |
| HFFI➣High-Frequency Flow Interruption Ventilation |
| HFFI➣High-Frequency Pneumatic Flow Interrupter |