| Rank | Abbreviation | Meaning |
|---|
| ***** | MHAA | Mental Health Act Administrator
| |
| ***** | MHAA | Miniature Horse Association Australia
| |
| ***** | MHAA | Miniature Horse Association of Arizona
| |
| ***** | MHAA | Miniature Horse Association of Australia, Inc.
| |
| ***** | MHAA | Mid-Hudson Astronomy Association
| |
| ***** | MHAA | Myanmar Health Assistant Association
| |
| ***** | MHAA | Manhours per Adjusted Admission
| |
| ***** | MHAA | Morgan Horse Association of Australia
| |
| ***** | MHAA | Maryland Heights Athletic Association
| |
| **** | MHAA | Mental Health Association of Arizona
| |
| **** | MHAA | Mark Hutker Associates Architects
| |
| **** | MHAA | Metropolitan Health Administrators Association
| |
| *** | MHAA | Mental Health Association of Alaska
| |
| *** | MHAA | monfort heights athletic association
| |
| *** | MHAA | Maryland Heritage Area Authority
| |
| *** | MHAA | McKinney Homeless Assistance Act
| |
| *** | MHAA | Monterey History and Art Association
| |
| *** | MHAA | Mental Health Association in Atlantic
| |
| *** | MHAA | Mid Hudson Animal Aid
| |
| *** | MHAA | Mechanical Harvesters Association of Australia
| |
| ** | MHAA | Mid Hudson Astronomical Association
| |
| ** | MHAA | Mile High Adventist Academy
| |
| ** | MHAA | Metropolitan Healthcare Administrators Association
| |
| ** | MHAA | Minot Hebron Athletic Association
| |
| * | MHAA | Mental Health Association of Augusta
| |