HIO
| Acronym | Definition |
|---|---|
| HIO | Hole-In-One (chiropractic) |
| HIO | Halt Input Output |
| HIO | Health Insuring Organization |
| HIO | Hire Immigrants Ottawa (Canada) |
| HIO | Health Information Organization |
| HIO | Harvard International Office |
| HIO | Horse Industry Organization |
| HIO | Hogere Informatica-Opleiding |
| HIO | High Income Opportunities |
| HIO | Horse Inspection Organization (inspects walking horses at horse shows) |
| HIO | High Intensity Operations |