| FSGS | focal segmental glomerulosclerosis |
|---|---|
| FSH | fascioscapulohumeral; focal and segmental hyalinosis; follicle-stimulating hormone |
| FSS | focal segmental sclerosis; Freeman-Sheldon syndrome; French steel sound |
| FTBE | focal tick-borne encephalitis |
| FZ | focal zone; furazolidone |