| Acronym | Definition |
|---|
| PHAI➣Public Health Advocacy Institute (Boston, Massachusetts) |
| PHAI➣Port Hope Area Initiative (est. 2001; Canada) |
| PHAI➣Passive House Association of Ireland |
| PHAI➣Panasonic Home Appliances India Co. Ltd. |
| PHAI➣Public Health Alliance Ireland (now Public Health Alliance for the Island of Ireland; est. 2006) |
| PHAI➣Phainopepia (bird species Phainopepla nitens) |