| FERTILEST | • fertilest adj. Superlative form of fertile: most fertile. • FERTILE adj. productive. |
| FILTRATES | • filtrates v. Third-person singular simple present indicative form of filtrate. • FILTRATE v. to filter. |
| FLIRTIEST | • flirtiest adj. Superlative form of flirty: most flirty. • FLIRTY adj. lightheartedly amorous, also FLIRTISH. |
| FLITTERNS | • flitterns n. Plural of flittern. • FLITTERN n. bark obtained from young oak trees. |
| FLUSTRATE | • flustrate v. (Colloquial) To fluster. • FLUSTRATE v. (obsolete) to fluster. |
| FRONTLETS | • frontlets n. Plural of frontlet. • FRONTLET n. a forehead ornament worn as a phylacteric, defending against disease. |
| FRONTLIST | • frontlist n. (Publishing) A list of the most recent books available from a publisher, as opposed to the backlist of older titles. • FRONTLIST n. a list of books about to be published. |
| FRUITLETS | • fruitlets n. Plural of fruitlet. • FRUITLET n. a small fruit. |
| STAIRLIFT | • stairlift n. A motorized platform installed in a stairway, which traverses the stairs when activated and can be ridden… • stair␣lift n. Alternative spelling of stairlift. • STAIRLIFT n. a lift to enable people to get up the stairs. |
| STREETFUL | • streetful n. As much as a street will hold. • STREETFUL n. the contents of a street. |
| THIRSTFUL | • thirstful adj. Thirsty. • THIRSTFUL adj. thirsty. |
| THRUSTFUL | • thrustful adj. Tending to thrust oneself forward; pushy. • THRUSTFUL adj. pushy, assertive. |
| ULTRAFAST | • ultrafast adj. Very fast, or of very short duration; especially concerning events that take place in femtosecond or… • ultra-fast adj. Alternative form of ultrafast. • ULTRAFAST adj. very fast. |
| ULTRASOFT | • ultrasoft adj. Extremely soft; of utmost softness. • ultrasoft adj. (Motorsports) Softer than supersoft, and harder than hypersoft. • ultrasoft n. (Motorsports) Ellipsis of ultrasoft tyre. |