| extraneous | Irrelevant or unrelated to the subject being dealt with | |
| exult | To show or feel a lively or triumphant joy; rejoice exceedingly; be highly elated or jubilant | |
| fabricate | To make or create something by assembling parts or components | |
| facetious | Treating serious issues with deliberately inappropriate humor; flippant | |
| fanatic | A person filled with excessive and single-minded zeal, especially for an extreme religious or political cause | |
| fastidious | Very attentive to and concerned about accuracy and detail | |
| fatuous | silly and pointless | |
| fecund | Capable of producing an abundance of offspring or new growth; fertile | |
| feign | To pretend to be affected by a feeling, state, or injury | |
| ferret | A domesticated, usually albino, variety of the polecat, used especially for hunting rabbits | |