Fly v. i. [imp. Flew p. p. Flown p. pr. & vb. n. Flying.]
 1. To move in or pass through the air with wings, as a bird.
 2. To move through the air or before the wind; esp., to pass or be driven rapidly through the air by any impulse.
 3. To float, wave, or rise in the air, as sparks or a flag.
    Man is born unto trouble, as the sparks fly upward.   --Job v. 7.
 4. To move or pass swiftly; to hasten away; to circulate rapidly; as, a ship flies on the deep; a top flies around; rumor flies.
    Fly, envious Time, till thou run out thy race.   --Milton.
    The dark waves murmured as the ships flew on.   --Bryant.
 5. To run from danger; to attempt to escape; to flee; as, an enemy or a coward flies. See Note under Flee.
    Fly, ere evil intercept thy flight.   --Milton.
    Whither shall I fly to escape their hands ?   --Shak.
 6. To move suddenly, or with violence; to do an act suddenly or swiftly; -- usually with a qualifying word; as, a door flies open; a bomb flies apart.
 To fly about Naut., to change frequently in a short time; -- said of the wind.
 To fly around, to move about in haste. [Colloq.]
 To fly at, to spring toward; to rush on; to attack suddenly.
 To fly in the face of, to insult; to assail; to set at defiance; to oppose with violence; to act in direct opposition to; to resist.
 To fly off, to separate, or become detached suddenly; to revolt.
 To fly on, to attack.
 To fly open, to open suddenly, or with violence.
 To fly out. (a) To rush out. (b) To burst into a passion; to break out into license.
 To let fly. (a) To throw or drive with violence; to discharge. “A man lets fly his arrow without taking any aim.” --Addison. (b) Naut. To let go suddenly and entirely; as, to let fly the sheets.