- fixed coil
- fixed contact
- fixed delay
- fixed load
- fixed loss
- fixed pole
- fixture
- fixture pair
- flame detector
- flame welding
- flame-retardant
- flammability
- flammability test
- flange motor
- flanged
- flanged radiator
- flare fitting
- flash
- flash barrier
- flash bulb
- flash gas
- flash point
- flash socket
- flash test
- flashing
- flashover
- flashover test
- flat cable
- flat coal
- flat relay
- flexible cable
- flexible conductor
- flexible disk
- flexible stranding
- flit plug
- floating
- Floating charge
- floating output
- floating potential
- floating trickle
- flooded system
- floor switch
- flue
- fluidized gasification
- flush-mounting
- foamed plastic
- focusing electrode
- fog lamp
- flat wire
- flat-compounded
- floodlight
- floor warming
- focusing coil
- focusing lamp
- follow current
- forbidden region
- forced outage
- Forecasting
- forest zone
- flue blower
- flue gas
- fluid
- fluid ounce
- fluidity
- fluoroscopy
- flush wiring
- flux density
- flux line
- flux linkage
- foaming
- floating battery
- floating input
- floodlighting
- flow
- flow switch
- fluctuating current
- fluctuation
- flue dust
- fluidized bed
- fluorescent tube
- flush switch
- flux leakage
- flux unit
- focusing anode
- focusing magnet
- fog light
- fold over
- foot switch
- foot-candle
- foot-lambert
- foot-pound
- formatted
- formed plate
- forward bias
- forward current
- forward period
- forwards bias
- Foucault current
- Fourier analysis
- Fourier theorem