- Four-legged Adj.
- Four-letter Subst. Adj.
- Four-poster Subst. Adj.
- Four-sided Adj.
- Four-star Adj. Subst.
- Four-year Adj.
- Fourchette Subst. Adj.
- Fourflusher Subst. Adj.
- Fourfold Adj. Adv.
- Fourier Subst. Eigenn. Adj.
- Fourmarierite Subst. Adj.
- Fourpenny Adj. Subst.
- Fourplex Subst. Adj.
- Fourpolar Adj.
- Fourposter Subst. Adj.
- Fourscore Adj. Subst. Num.
- Foursided Adj.
- Foursome Subst. Adj.
- Foursquare Adj. Subst. Adv.
- Fourteener Subst. Adj.
- Fourway Adj. Subst. Adv.
- Foveal Adj.
- Foveated Adj. Part. Perf.
- Foveolar Adj.
- Fowl Subst. Verb Adj.
- Fowlerite Subst. Adj.
- Fox Subst. Verb Adj. Eigenn. Part. Perf.
- Foxed Adj.
- Foxglove Subst. Adj.
- Foxhole Subst. Adj.
- Foxhound Subst. Adj.
- Foxhunt Subst. Verb Adj.
- Foxlike Adj.
- Foxskin Subst. Adj.
- Foxtail Subst. Adj.
- Foxtrot Subst. Verb Adj.
- Foxy Adj. Subst.
- Foyaite Subst. Adj.
- Foyer Subst. Adj.
- FPGA Subst. Adj.
- Frabjous Adj.
- Frack Subst. Verb Adj. Inter.
- Fracking Subst. Adj.
- Fractal Adj. Subst.
- Fractile Adj. Subst.
- Fraction Subst. Verb Adj.
- Fractional Adj. Subst.
- Fractionary Adj.
- Fractionated Adj.
- Fractionator Subst. Adj.
- Fractious Adj.
- Fractocumulus Subst. Adj.
- Fractostratus Subst. Adj.
- Fracture Subst. Verb Adj.
- Fractured Adj.
- Frag Subst. Verb Adj.
- Fragged Adj.
- Fragile Adj.
- Fragility Subst. Adj.
- Fragment Subst. Verb Adj.