| BFEC | benign focal epilepsy of childhood |
|---|---|
| EFL | effective focal length |
| FCD | feces collection device; fibrocystic disease; fibrocystic dysplasia; focal cytoplasmic degradation |
| FD | familial dysautonomia; family doctor; fan douche; fatal dose; fetal danger; fibrin derivative; fibro... |
| FDH | familial dysalbuminemic hyperthyroxinemia; focal dermal hypoplasia; formaldehyde dehydrogenase |
| focal spot | The site of bombardment by electrons and emission of X-rays from the anode of an X-ray tube. See: focal spot size. (05 Mar 2000) |
|---|---|
| focal spot size | The measured size of a focal spot, a function of its actual size and the angulation of the anode surface. See: focal spot. (05 Mar 2000) |