| flung |
past tense and past participle of "fling." |
| fluorescent |
able to give off visible light after being exposed to a source of heat, light, or other form of energy. |
| fluoridate |
to add a fluoride to, in order to keep teeth healthy. |
| fluoride |
a chemical compound that contains fluorine as one of its elements. |
| fluorine |
a substance that is a chemical element. Fluorine combines easily with other elements to form compounds. Some of these compounds are used to prevent tooth decay. Fluorine is poisonous in its pure gas form. (symbol: F) |
| flurry |
a light fall of snow that ends quickly. [2 definitions] |
| flush1 |
a brief, heavy flow of water or other liquid. [7 definitions] |
| flush2 |
even or level with another surface or line. [2 definitions] |
| fluster |
to cause to become nervous, confused, or upset. [2 definitions] |
| flute |
a woodwind instrument with a high pitch. It is a long tube with finger holes or keys along it and is played by blowing into a hole near one end. |
| flutter |
to wave rapidly back and forth or up and down. [5 definitions] |
| fly1 |
to move through the air by means of wings. [9 definitions] |
| fly2 |
an insect with two wings. Most flies are active in the daytime, and many have large eyes. Mosquitoes and houseflies are among the thousands of types of flies. |
| flycatcher |
a bird that lives in Europe and America and eats insects that it catches in the air. There are many different kinds of flycatchers. |
| flying |
being able to fly or seeming to fly. [4 definitions] |
| flying fish |
a fish that lives in the ocean and has fins that look like wings. Flying fish can glide in the air after jumping from the water. |
| flying saucer |
a bright, flying object shaped like a disk that some people believe is a spacecraft from another world; UFO. |
| fly off the handle |
to become very angry; lose one's temper (an informal use). |
| foal |
a young horse, donkey, or related animal, usually one that is less than a year old. [2 definitions] |
| foam |
a mass of small bubbles that forms on the surface of a liquid. [6 definitions] |
| foam rubber |
a firm, light rubber that feels like sponge. Foam rubber is often used to make cushions and mattresses. |