| fitful | Not steady; irregular or spasmodic | |
| finagled | Obtained by trickery or craftiness | |
| fiasco | A complete failure, especially a ludicrous or humiliating one | |
| fetid | smelling extremely unpleasant | |
| festoon | A chain or garland of flowers, leaves, or ribbons, hung in a curve as a decoration | |
| ferret | A domesticated, usually albino, variety of the polecat, used especially for hunting rabbits | |
| feign | To pretend to be affected by a feeling, state, or injury | |
| fecund | Capable of producing an abundance of offspring or new growth; fertile | |
| fatuous | silly and pointless | |
| fastidious | Very attentive to and concerned about accuracy and detail | |