| FIS | forced inspiratory spirogram; free induction signal |
|---|---|
| FIV | feline immunodeficiency; forced inspiratory volume |
| FIV1 | forced inspiratory volume in one second |
| FMF | familial Mediterranean fever; fetal movement felt; flow microfluorometry; forced midexpiratory flow |
| FO | fiberoptic; fish oil; foot arthrosis; foramen ovale; forced oscillation; fronto-occipital |