| FFE | fast field echo; fecal fat excretion |
|---|---|
| FOB | fecal occult blood; feet out of bed; fiberoptic bronchoscopy; foot of bed; functional observational ... |
| FOBT | fecal occult blood test |
| FU | fecal urobilinogen; fetal urobilinogen; fluorouracil; follow-up; flux unit [ion]; fractional urinaly... |
| KF | Kenner-fecal medium; kidney function; Klippel-Feil [syndrome] |