FNIS
| Acronym | Definition |
|---|---|
| FNIS | Fidelity National Information Services (Jacksonville, FL) |
| FNIS | Fidelity National Information Solutions (Santa Ana, CA) |
| FNIS | Foreign National Information System (student registration) |
| FNIS | Fast Neutron Irradiation System (physics) |
| FNIS | First Nations Interdisciplinary Studies (Canada) |