fly 1 (flī)
v. flew (fl), flown (flōn), fly·ing, flies (flīz)
1. To engage in flight, especially:
a. To move through the air by means of wings or winglike parts.
b. To travel by air: We flew to Dallas.
c. To operate an aircraft or spacecraft.
a. To rise in or be carried through the air by the wind: a kite flying above the playground.
b. To float or flap in the air: pennants flying from the masthead.
3. To move or be sent through the air with great speed: bullets flying in every direction; a plate that flew from my hands when I stumbled.
a. To move with great speed; rush or dart: The children flew down the hall.
b. To be communicated to many people: Rumors are flying about their breakup.
c. To flee; escape.
d. To hasten; spring: flew to her students' defense.
5. To pass by swiftly: a vacation flying by.
6. To be dissipated; vanish: All his money has flown.
7. past tense and past participle flied (flīd) Baseball To hit a fly ball.
a. To shatter or explode: The dropped plate flew into pieces.
b. To become suddenly emotional, especially angry: The driver flew into a rage.
9. Informal To gain acceptance or approval; go over: "However sophisticated the reasoning, this particular notion may not fly" (New York Times).
a. To cause to fly or float in the air: fly a kite; fly a flag.
b. Nautical To operate under (a particular flag): a tanker that flies the Liberian flag.
a. To pilot (an aircraft or spacecraft).
b. To carry or transport in an aircraft or spacecraft: fly emergency supplies to a stricken area.
c. To pass over or through in flight: flew the coastal route in record time.
d. To perform in a spacecraft or aircraft: flew six missions into space.
a. To flee or run from: fly a place in panic.
b. To avoid; shun: fly temptation.
n. pl. fliesPhrasal Verb:
1. The act of flying; flight.
a. The opening, or the fastening that closes this opening, on the front of a pair of pants.
b. The flap of cloth that covers this opening.
3. A piece of protective fabric secured over a tent and often extended over the entrance.
4. A flyleaf.
5. Baseball A fly ball.
6. Sports In swimming, butterfly.
a. The span of a flag from the staff to the outer edge.
b. The outer edge of a flag.
8. A flywheel.
9. flies The area directly over the stage of a theater, containing overhead lights, drop curtains, and equipment for raising and lowering sets.
10. Chiefly British A one-horse carriage, especially one for hire.
To attack fiercely; assault: The dogs flew at each other's throats.
To be elated: They were flying high after their first child was born.
fly off the handle Informal
To become suddenly enraged: flew off the handle when the train was finally canceled.
1. To shoot, hurl, or release: The troops let fly a volley of gunfire.
2. To lash out; assault: The mayor let fly with an angry attack on her critics.
on the fly
1. In a hurry or between pressing activities: took lunch on the fly.
2. While moving: The outfielder caught the ball on the fly.
3. In the air; in flight: The ball carried 500 feet on the fly.
4. While activity is ongoing: A coach can change players on the fly in hockey. This computer program compiles on the fly when a script is executed.
[Middle English flien, from Old English flēogan; see pleu- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.