| Acronym | Definition |
|---|
| HATT➣Help Authoring Tools and Techniques (web forum) |
| HATT➣High All the Time |
| HATT➣Hanung Toys and Textiles Limited (India; toy manufacturing) |
| HATT➣Hands across the Trail (Appalachian Trail event) |
| HATT➣Heparin-Associated Thrombocytopenia with Thrombosis (biomedicine) |
| HATT➣Himpunan Alumni Timur Tengah (Indonesian: Alumni Association of the Middle East) |