| M.I.O. | Medical Information Officer 
| Others |
| MIO | Made in Oklahoma
| Others |
| MIO | Magnetic Iron Oxide
| Others |
| MIO | Make it Own
| Others |
| MIO | Managed Input Output
| Others |
| MIO | Management Information Office
| Others |
| MIO | Management Integration Office
| Others |
| MIO | Mandated Iwi Organisation
| Others |
| MIO | Many Independent Objective
| Others |
| MIO | Marine Inspection Operations
| Others |
| MIO | Maritime Interception Operations
| Others |
| MIO | Maritime Interdiction Operation
| Others |
| MIO | Maritime Interdiction Operations
| Others |
| MIO | Mask Input Output
| Others |
| MIO | Masked Input Output
| Others |
| MIO | Medically Improved Outcomes
| Others |
| MIO | Mediterranean Information Office for Environment, Culture, and Sustainable Development
| Others |
| MIO | Memory Input Output
| Others |
| MIO | MIAMI Municipal Airport, Miami, Oklahoma
| Others |
| MIO | Micaceous Iron Oxide
| Others |
| MIO | Micaeous Iron Oxide
| Others |
| MIO | million ( Swiss)
| Others |
| MIO | Million/Millions
| Others |
| Mio | Millionen
| Others |
| MIO | Mobile I O
| Others |
| MIO | Mobile Ideal Original
| Others |
| MIO | Modular Individual Organised
| Others |
| MIO | Modular Input Output
| Others |
| MIO | Module Input Output
| Others |
| MIO | More In One
| Others |
| MIO | Motility indole ornithine
| Others |
| MIO | Motivation Inspiration and Opportunity
| Others |
| MIO | Multimedia Information Organizer
| Others |
| MIO | My Input Output
| Others |
| MIO | My intelligent OrganizationMiO
| Others |