- ferromagnetic
- ferrule
- fertile isotope
- fibre axis
- field equation
- fifth
- fill-in
- field flutter
- field stop
- field weld
- filling material
- film clip
- film dryer
- film shrinkage
- filter run
- filter support
- filtration pressure
- finder hood
- filter house
- final assembly
- finder
- fire ball
- fire curtain
- fire lobby
- fire stop
- fire-retarding
- firm capacity
- first criticality
- first divergence
- fision
- fissile isotope
- fissile material
- fission
- fission energy
- fission fragments
- fission heat
- fission neutrons
- fission recoil
- fission spike
- fissionable
- fissure vein
- fixed focus
- fixing
- fixing agent
- fixing thread
- fixity
- Fizeau fringes
- flame hydrolysis
- flame spectroscopy
- flame tube
- flameproof stirrer
- flap
- flash
- flash bar
- flash contact
- flash cooling
- flash cube
- flash duration
- flash shoe
- flash switch
- flash-harden
- flast
- flat
- flat lighting
- flattening test
- flexible drive
- flicker photometer
- flood
- flow resistance
- fluid friction
- focal aperture
- focus setting
- focused beam
- fog
- flexural vibration
- focusing screen
- focusing stage
- folding camera
- forbidden transition
- force
- force direction
- force fit
- forced draft
- forced oscillation
- fork
- flow cup
- flow resistivity
- fluid dynamics
- fluid engineering
- fluid pressure
- fluid waves
- fluoresce
- flush lens
- flutter
- flux
- flux guide
- focus
- focusing range
- flow
- flow visualization