| Term | Definition |
| fallen | having dropped by the force of gravity |
| fallible | adj.-liable to error, being mislead or deceived, false |
| families | elements that have things in common with each other |
| family | primary social group |
| farce | a comedy characterized by broad satire and improbable situations |
| farmer | a person who operates a farm |
| fatigue | temporary loss of strength and energy resulting from hard physical or mental work |
| favorite | best liked |
| fax | Telephonic transmission of scanned-in printed material |
| February | The second month of the year |
| federal | of or relating to the central government of a federation |
| festivals | were to honor the gods |
| feud | a state of prolonged mutual hostility, typically between two families or communities |
| fibrin | a white insoluble fibrous protein formed by the action of thrombin on fibrinogen when blood clots |
| fickle | unpredictable; whimsical; easily swayed |
| field | a branch of knowledge |
| field trip | a group excursion (to a museum or the woods or some historic place) for firsthand examination |
| fierce | menacingly wild, savage, or hostile |
| finally | as the end result of a succession or process |
| firebrand | a piece of burning wood; a troublemaker; and extremely energetic or emotional person |
| firefighter | a member of a fire department who tries to extinguish fires |
| fireworks | explosions set off to create bright lights and colorful displays for entertainment |
| fixed joint | a joint that does not move, found in skull only |
| flagrant | adj. Openly scandalous. |
| flaw | an imperfection; a defect |
| fledgling | an inexperienced person, beginner; a young bird about to leave the nest; inexperienced, budding |
| floss | a soft thread for cleaning the spaces between the teeth |
| flounder | struggle and thrash about; proceed clumsily or falter (as in water, mud, snow, etc.); proceed in confusion |
| flour | fine powdery foodstuff obtained by grinding and sifting the meal of a cereal grain |
| flourish | to thrive or prosper; to wave in the air; a sweeping motion; a showy burst of music; a fancy line or curve added to something written |
| flourishes | grow well; prosper; make sweeping gestures; wave; brandish; Ex. The trees flourished in the sun. N: showy movement or gesture; embellishment or ornamentation (esp. in handwriting) |
| fluctuate | move or sway in a rising and falling or wavelike pattern |
| fluorescent | brilliantly colored and apparently giving off light |
| fluoride | a salt of hydrofluoric acid |
| fluster | to make or become confused, agitated, or nervous; a state of confusion or agitation |
| foodchain | the relationship between feeding organisms |
| foreign | Of, pertaining to, or derived from another country or nation; not native. |
| foremost | first in rank, time, place, position |
| foretaste | (n) an advance indication, sample, or warning |
| forgive | to stop blaming or being angry with someone for something they have done, or not punish them for something |
| forgotten | to cease or fail to remember; be unable to recall |
| formally | with official authorization |
| formerly | in an earlier period; previously |
| forty | the cardinal number that is the product of ten and four |
| foster | providing or receiving nurture or parental care though not related by blood or legal ties |
| fracture | break (a bone) |
| French fries | strips of potato fried in deep fat |
| friends | non-family people whom we like and are close to |
| frightened | thrown into a state of intense fear or desperation |
| frostbite | a condition that results when body tissues become frozen |
| fruitless | not producing the desired results, unsuccessful |
| frustrate | to prevent from accomplishing a purpose of fulfilling a desire; to cause feelings of discouragement |
| fuel | a substance that provides a form of energy as a result of a chemical change |
| fugitive | someone who is sought by law officers |
| fulfill | to carry out, or bring to realization, as a prophecy or promise. |
| funeral | a ceremony at which a dead person is buried or cremated |
| fungi | mushrooms |
| futile | useless; hopeless; ineffectual |