- Framingham Risk Score
- Francis turbine
- Francisella tularensis
- Franck-Condon principle
- Francolite
- Franklinite
- Fraunhofer diffraction
- Frax
- Frazil ice
- Fredholm alternative
- Fredholm integral equation
- Fredholm operators
- Fredkin gate
- Free acidity
- Free base
- Free body
- Free body diagram
- Free boundary problems
- Free cooling
- Free electron model
- Free energy perturbation
- Free energy principle
- Free entropy
- Free field
- Free flap
- Free flight
- Free float
- Free lattice
- Free list
- Free module
- Free molecular flow
- Free particles
- Free radical damage
- Free radical reaction
- Free radicals
- Free spectral range
- Free surface
- Free surface effect
- Free variables
- Free water
- Free-electron laser
- Free-energy relationship
- Free-form deformation
- Free-piston engine
- Free-radical addition
- Free-radical reaction
- Free-space optical communication
- Free-space path loss
- FreeRTOS
- Freebase
- Freestream
- Freesurfer
- Freeware
- Freeze drying
- Freeze thaw resistance
- Freeze-casting
- Freeze-dried
- Freeze-thaw
- Freezing
- Freezing-point depression
- Freibergite
- Freight forwarders
- Freight rate
- Freight terminal
- Freight trains
- French drain
- Frenetic
- Frenkel defect
- Freon
- Frequency
- Frequency allocation
- Frequency analysis
- Frequency band
- Frequency comb
- Frequency compensation
- Frequency coordination
- Frequency counters
- Frequency deviation
- Frequency distribution
- Frequency divider
- Frequency domain
- Frequency drift
- Frequency grid
- Frequency hopping
- Frequency meter
- Frequency mixer
- Frequency multiplier
- Frequency response
- Frequency scaling
- Frequency selective surface
- Frequency spectrum
- Frequency standards
- Frequency synthesizer
- Frequency-locked loop
- Frequent urination
- Frequentist
- Frequentist inference
- Fresh water
- Freshets
- Freshwater
- Freshwater ecosystems
- Fresnel
- Fresnel diffraction
- Fresnel equations
- Fresnel lens
- Fresnel number
- Fresnel reflectors
- Fresnel zone
- Freund's adjuvant
- Friability
- Friable
- Friction
- Friction drilling
- Friction drive
- Friction loss
- Friction modifier
- Friction of distance
- Friction sensitivity
- Friction stir processing
- Friction stir spot welding
- Friction stir welding
- Friction torque
- Friction velocity
- Friction welding
- Friedel oscillations
- Friedman test
- Friendship graph
- Fries rearrangement
- Friis transmission equation
- Fringe shift
- Frit
- Fritted glass
- Fritzing
- Frizzled
- Frobenius method
- Frobenius norm
- Frobenius theorem
- Front panel
- Front-end processors
- Front-to-back ratio
- Front-wheel drive
- Frontal bone
- Frontal eye fields
- Frontal gyri
- Frontal gyrus
- Frontal lobe
- Frontal lobe epilepsy
- Fronthaul
- Frontier molecular orbital theory
- Frontoparietal network