| 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 seats and mattresses. |
| focus |
the point at which rays of light or heat come together or from which they seem to move away. [6 definitions] |
| fodder |
feed for farm animals, such as stalks of corn cut and mixed with hay. |
| foe |
one who wishes ill on another; personal enemy. |
| fog |
a thick mass, like a cloud, made up of tiny water drops floating in the air near the ground; mist. [4 definitions] |
| foggy |
full of or covered by fog. [2 definitions] |
| foghorn |
a loud, deep horn on a ship or on the shore, used in fog or at night to give warning signals. |
| foil2 |
a very thin, flexible sheet of a metal, such as aluminum. |
| -fold |
a suffix that means "multiplied by" or "times." [2 definitions] |
| fold1 |
to bend over upon itself so that one section lies on or against another section. [8 definitions] |
| fold2 |
an area within a fence or wall where sheep or other animals are kept. |