| FFR | Freedom from relapse |
|---|---|
| FFR | Frequency following response |
| FFS | Failure-free survival |
| FFS | Fee-For-Service |
| FFT | Fast Fourie Transform |
| FFT | Fast Fourier 'Transformation |
| FFTF | Freedom-from-treatment-failure |
| FFU | focus forming units |
| FFW | Fat free weight |
| FFWI | fusion from within |