| flounder | To struggle clumsily or helplessly | |
| flourish | To grow or develop in a healthy or vigorous way, especially as the result of a particularly favorable environment | |
| flouted | To show contempt for a law or convention by openly disobeying or defying it | |
| fluctuate | To rise and fall irregularly in number or amount | |
| flummoxed | bewildered or perplexed | |
| foible | A minor weakness or eccentricity in someone's character | |
| foment | To instigate or stir up an undesirable or violent sentiment, action, or situation | |
| forbearance | Patient self-control; restraint and tolerance under provocation | |
| foreground | The part of a view that is nearest to the observer, especially in a picture or photograph | |
| forestall | To prevent or obstruct an anticipated event or action by taking action ahead of time | |