HHMM
| Acronym | Definition |
|---|---|
| HHMM | Hierarchical Hidden Markov Model |
| HHMM | Healthcare Hazard Management Monitor |
| HHMM | Hour Hour Minute Minute (time format) |
| HHMM | Hermanos Maristas (Spanish private school) |
| HHMM | Helping Hands Medical Missions (various locations) |