| FR | failure rate; film-screen radiograph; fasciculus retroflexus; febrile reaction; feedback regulation;... |
|---|---|
| FW | Felix-Weil [reaction]; Folin-Wu [reaction]; fragment wound |
| FWR | Felix-Weil reaction; Folin-Wu reaction |
| IAR | immediate asthma reaction; inhibitory anal reflex; iodine-azide reaction |
| IR | drop of voltage across a resistor produced by a current; ileal resection; immune response; immunizat... |