Emily Dickinson Lexicon

FLY, n. [Sax. fleoge; Sw. fluga; Dan. flue; G. fliege; D. vlieg; from the verb, fleogan, to fly.]

1. In zoology, a winged insect of various species, whose distinguishing characteristic is that the wings are transparent. By this flies are distinguished from beetles, butterflies, grasshoppers, &c. Of flies, some have two wings and others four. – Encyc. In common language, fly is the house fly, of the genus Musca.
2. In mechanics, a cross with leaden weights at the ends, or a heavy wheel at right angles with the axis of a windlass, jack or the like. The use of this is, to regulate and equalize the motion in all parts of the revolution of the machine. – Encyc.
3. That part of a vane which points and shows which way the wind blows.
4. The extent of an ensign, flag or pendant from the staff to the end that flutters loose in the wind. – Mar. Dict.