HAHA
| Acronym | Definition |
|---|---|
| HAHA | Having A Heart Attack |
| HAHA | Human Anti-Human Antibody |
| HAHA | Huntsville Amateur Hockey Association (Huntsville, AL) |
| HAHA | Houston Area Hound Association (Texas) |
| HAHA | Health and Humor Associates (Stamford, CT) |
| HAHA | Human-Anti-Humanized Antibodies (immunogenicity testing assay) |