| Acronym | Definition |
|---|
| FON | Phone |
| FON | Fakultet Organizacionih Nauka (Serbian: Faculty of Organizational Sciences) |
| FON | Font File (Microsoft file extension) |
| FON | Faculty of Nursing (various locations) |
| FON | Freedom of Navigation (operations; US DoD) |
| FON | Fiber Optics Network |
| FON | Font File |
| FON | Full of Noises (music) |
| FON | Funding Opportunity Number (grants) |
| FON | Fiber Optic Network |
| FON | Force of Nature (gaming) |
| FON | Freak of Nature |
| FON | Freedom of Navigation (territorial waters permissions) |
| FON | Firm Order Noted |
| FON | Fuel Oil News (magazine) |
| FON | Phone/Phone Directory (File Name Extension) |
| FON | Fibres Optiques Noires (French: Dark Fibre Optics) |
| FON | Friends of Nancy |
| FON | Forest Outreach Network (King County, Washington) |
| FON | Friends of Nature for Better Environment |
| FON | Fiber-Optic News |