- first-former
- first-generation
- firsthand
- firstly
- first-nighter
- first-past-the-post
- first-rate
- first-strike
- first-time
- firth
- fiscal
- fish
- fish eagle
- fish factory
- fish farm
- fish farmer
- fish farming
- fish finger
- fish glue
- fish hook
- fish kettle
- fish ladder
- fish market
- fish meal
- fish paste
- fish sauce
- fish shop
- fish slice
- fish stick
- fish tank
- fish-and-chip shop
- fishbone
- fishbowl
- fishcake
- fisher
- fisherman
- fishery
- fish-eye lens
- fishing
- fishing boat
- fishing ground
- fishing line
- fishing net
- fishing rod
- fishmonger
- fishnet
- fishplate
- fishpond
- fishskin disease
- fishwife
- fishwrap
- fishy
- fissile
- fission
- fission bomb
- fission reactor
- fissionable
- fissure
- fissured
- fist
- fistfight
- fistful
- fisticuffs
- fistula
- fit
- fitful
- fitfully
- fitment
- fitness
- fitted
- fitter
- -fitting
- fitting
- fittingly
- fit-up
- five
- five and dime
- five spot
- five-a-side
- five-day week
- five-finger
- fivefold
- five-o'clock shadow
- fiver
- five-spice powder
- five-star
- five-year
- five-yearly
- fix
- fixated
- fixation
- fixative
- fixed
- fixedly
- fixed-price menu
- fixed-wing aircraft
- fixer
- fixing bath
- fixing solution
- fixings
- fixity
- fixture
- fizz
- fizziness
- fizzle
- fizzy
- fjord
- FL
- fl. oz.
- flab
- flabbergasted
- flabby
- flaccid
- flack
- flag
- flag day
- flag officer
- flagellant
- flagellate
- flagellation
- flagellum
- flagged
- flagging
- flagon
- flagpole
- flagrant
- flagrante delicto
- flagrantly
- flagship
- flagstaff
- flagstone
- flag-waving
- flail
- flair
- flak
- flake
- flakiness
- flaky
- flambé
- flamboyance
- flamboyant
- flamboyantly
- flame
- flame retardant
- flame war
- flame-coloured
- flame-grilled
- flamenco
- flameout
- flameproof
- flamethrower
- flaming
- flamingo
- flammable
- flan
- Flanders
- flange
- flanged
- flank
- flanker
- flannel
- flannelette
- flap
- flapjack
- flapper
- flare
- flare gun
- flare path
- flared
- flare-up
- flash
- flash burn
- flash card
- flash drive
- flash flood
- flash freezing
- flash gun
- flash Harry
- flash photography
- flashback
- flashbulb
- flashcube
- flasher
- flash-fry
- flashily
- flashing
- flashlight
- flashpoint
- flashy
- flask
- flat
- flat cap
- flat race
- flat racing
- flat season
- flat top
- flat-bed lorry
- flat-bed scanner
- flat-bottomed boat
- flat-chested