F - Failed 
F - farad 
F - Farenheit 
F - Fellow 
F - femto 
F - Filament of tubes 
F - Final 
F - Final bit 
F - Fixed 
F - Fixed length 
F - Fixed service 
F - Flag 
F - Flow 
F - Focal length 
F - Forecast 
F - Forward Compatibility 
F - Framing 
F - French 
f - frequency 
F - FTAM Service 
F - Fully Associated 
F - Future 
F key - Function key 
F Port - Fabric Port 
F-BCCH - Fast Broadcast Control Channe… 
F-ES - Fixed End System 
F-S - Fiat-Shamir 
F/B - Fuse Block 
F/D - Focal Length-to-Diameter 
F/O - Fiber Optics