A one-horse carriage, especially one for hire. Any of numerous two-winged insects of the order Diptera, especially any of the family Muscidae, which includes the housefly. Any of various other flying insects, such as the caddis fly. 2.A fishing lure simulating a fly, made by attaching materials such as feathers, tinsel, and colored thread to a fishhook. Other familiar flies are crane flies, gnats, black flies, horse flies, blow flies, fruit flies, and tsetse flies.
True flies possess only a single pair of wings.
Flies make up the fourth largest insect order, after the beetles, butterflies and moths, and bees and wasps. Physical Characteristics Flies have large compound eyes composed of thousands of individual lenses. The eyes are very sensitive to sudden movement. Most flies have highly developed mouthparts that are used for specialized feeding. Mosquitoes have piercing-sucking mouthparts and feed on blood and nectar.