| Acronym | Definition |
|---|
| MFO | Multinational Force and Observers (US DoD) |
| MFO | Mathematisches Forschungsinstitut Oberwolfach (German: Oberwolfach Mathematical Research Institute; est. 1944) |
| MFO | Matratzen Factory Outlet (German: Factory Matress Outlet) |
| MFO | Mixed Function Oxidase |
| MFO | Multi-Family Office |
| MFO | Marine Fuel Oil |
| MFO | Medium Fuel Oil |
| MFO | Michigan Film Office (Lansing, MI) |
| MFO | Municipal Finance Officer (various locations) |
| MFO | Men from Off (harmony group; UK) |
| MFO | Mace Francis Orchestra |
| MFO | Make Friends Online (dating website) |
| MFO | Mission Field Outreach (ministry) |
| MFO | Microfinance Organization |
| MFO | Male, Female, Other |
| MFO | Manufacturing Footprint Optimization (various companies) |
| MFO | Military Family Outdoor (Sierra Club) |
| MFO | Mazhar Fuat Özkan (band) |
| MFO | Melbourne Film Office (Australia) |
| MFO | Mr. Fixit Online (gamer site) |
| MFO | Must Finish On (project management) |
| MFO | Multiple Facility Organization |
| MFO | Maine Film Office |
| MFO | Multinational Force & Observers Medal |
| MFO | Market Facilitation Organization |
| MFO | Michael Fassbender Online (fansite) |
| MFO | Management Field Observation (various organizations) |
| MFO | Multicast Fan-Out |
| MFO | Multi-Function Oxidase (immunology) |
| MFO | Maintenance Free Operations |
| MFO | Materiel Fielding Operations |
| MFO | Master Frequency Oscillator |
| MFO | Multi-Frequency - Originating (telephony) |
| MFO | Maintenance Free Operating Period |
| MFO | Mandatory Family Outing |
| MFO | Medical Flight Officer |