fly

¹ American  

[flahy] / flaɪ /

noun

flies plural

1. Also called true fly.  any of numerous two-winged insects of the order Diptera, especially of the family Muscidae, as the common housefly.

2. any of various winged insects, as the mayfly or firefly.

3. Angling. a fishhook dressed with hair, feathers, silk, tinsel, etc., so as to resemble an insect or small fish, for use as a lure or bait.

4. Astronomy. Fly, the constellation Musca.

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idioms

1. fly in the ointment, a detrimental factor; detraction.

   If there's one fly in the ointment, it's that there may not be the money to finish the job.

fly ² American  

[flahy] / flaɪ /

verb (used without object)

flies, present (3rd person singular) flew, past flied, past participle, past flown, past participle flying present participle

1. to move through the air using wings.

2. to be carried through the air by the wind or any other force or agency.

   bits of paper flying about.

3. to float or flutter in the air.

   flags flying in the breeze.

4. to travel in an aircraft or spacecraft.

5. to move suddenly and quickly; start unexpectedly.

   He flew from the room.

6. to change rapidly and unexpectedly from one state or position to another.

   The door flew open.

7. to flee; escape.

8. to travel in space.

   The probe will fly past the planet.

9. to move or pass swiftly.

   How time flies!

10. to move with an aggressive surge.

    A mother fox will fly at anyone approaching her kits.

11. Baseball.

    1. to bat a fly ball.

       He flied into right field.

    2. to fly out.

12. Informal. to be acceptable, believable, or feasible.

    It seemed like a good idea, but it just wouldn't fly.

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verb (used with object)

flies, present (3rd person singular) flew, past flied, past participle, past flown, past participle flying present participle

1. to make (something) float or move through the air.

   to fly a kite.

2. to operate (an aircraft, spacecraft, or the like).

3. to hoist aloft, as for display, signaling, etc..

   to fly a flag.

4. to operate an aircraft or spacecraft over.

   to fly the Pacific.

5. to transport or convey by air.

   We fly merchandise to Boston.

6. to escape from; flee.

   to fly someone's wrath.

7. Theater.

   1. to hang (scenery) above a stage by means of rigging supported by the gridiron.

   2. to raise (scenery) from the stage or acting area into the flies.

noun

flies plural

1. a strip of material sewn along one edge of a garment opening for concealing buttons, zippers, or other fasteners.

2. a flap forming the door of a tent.

3. Also called tent fly.  a piece of canvas extending over the ridgepole of a tent and forming an outer roof.

4. an act of flying; a flight.

5. the course of a flying object, as a ball.

6. Baseball. fly ball.

7. British. a light, covered, public carriage drawn by one horse; hansom; hackney coach.

8. Machinery. a horizontal arm, weighted at each end, that pivots about the screw of a press so that when the screw is lowered the momentum of the fly will increase the force of the press.

9. Also called fan.  Horology. a regulating device for chime and striking mechanisms, consisting of an arrangement of vanes on a revolving axis.

10. Printing.

    1. (in some presses) the apparatus for removing the printed sheets to the delivery table.

    2. Also called flyboy.  (formerly) a printer's devil employed to remove printed sheets from a press.

11. (on a flag)

    1. the horizontal dimension of a flag as flown from a vertical staff.

    2. the end of the flag farther from the staff.

12. Also called fly loft.  Theater. flies. the space above the stage used chiefly for storing scenery and equipment.

13. Nautical. a propellerlike device streamed to rotate and transfer information on speed to a mechanical log.

verb phrase

1. fly out to be put out by hitting a fly ball that is caught by a player of the opposing team.

idioms

1. fly off the handle. handle.

2. fly blind,

   1. to operate an airplane, especially during conditions of poor visibility, relying solely on instruments for guidance.

   2. to proceed with a complex task in the absence of directions by using one's own ability to determine what procedures to follow.

3. fly in the face of, to act in defiance of (authority, custom, etc.). Also fly in the teeth of

4. go fly a kite,

   1. to put up with or get used to matters as they stand.

   2. to confine oneself to one's own affairs.

   3. to cease being a nuisance.

      If she gets mad enough she'll tell me to go fly a kite.

5. on the fly,

   1. during flight; before falling to the ground.

      to catch a baseball on the fly.

   2. hurriedly; without pausing.

      We had dinner on the fly.

6. let fly,

   1. to hurl or propel (a weapon, missile, etc.).

   2. to give free rein to an emotion.

      She let fly with a barrage of angry words.

fly ³ American  

[flahy] / flaɪ /

adjective

flyer, flyest

1. Slang. stylish, attractive, sophisticated, etc..

   She put on silver stilettos, her flyest outfit, and plenty of bling, ready to party till dawn.

2. British Slang. aware and worldly; clever; smart.

   Adults generally found him sly and conniving, but his teenage followers were convinced he was fly.

3. British Slang. dexterous; agile; nimble.

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fly ¹ British  

/ flaɪ /

adjective

1. knowing and sharp; smart

2. furtive or sneaky

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noun

1. in secret; sneakily

fly ² British  

/ flaɪ /

noun

1. any dipterous insect, esp the housefly, characterized by active flight See also horsefly blowfly tsetse fly crane fly

2. any of various similar but unrelated insects, such as the caddis fly, firefly, dragonfly, and chalcid fly

3. angling a lure made from a fish-hook dressed with feathers, tinsel, etc, to resemble any of various flies or nymphs: used in fly-fishing See also dry fly wet fly

4. (in southern Africa) an area that is infested with the tsetse fly

5. slang to drink alone

6. See amber

7. informal a slight flaw that detracts from value, completeness, or enjoyment

8. a person who watches others, while not being noticed himself or herself

9. informal he is no fool

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fly ³ British  

/ flaɪ /

verb

1. (intr) (of birds, aircraft, etc) to move through the air in a controlled manner using aerodynamic forces

2. to travel over (an area of land or sea) in an aircraft

3. to operate (an aircraft or spacecraft)

4. to float, flutter, or be displayed in the air or cause to float, etc, in this way

   to fly a kite

   they flew the flag

5. to transport or be transported by or through the air by aircraft, wind, etc

6. (intr) to move or be moved very quickly, forcibly, or suddenly

   she came flying towards me

   the door flew open

7. (intr) to pass swiftly

   time flies

8. to escape from (an enemy, place, etc); flee

   he flew the country

9. (intr; may be foll by at or upon) to attack a person

10. (intr) to have a sudden outburst

    he flew into a rage again

11. (intr) (of money, etc) to vanish rapidly

12. (tr) falconry (of hawks) to fly at (quarry) in attack

    peregrines fly rooks

13. (tr) theatre to suspend (scenery) above the stage so that it may be lowered into view

14. 1. to procure money by an accommodation bill

    2. to release information or take a step in order to test public opinion

15. informal

    1. to have a high aim

    2. to prosper or flourish

16. See face

17. informal to lose one's temper

18. informal to leave suddenly

19. informal go away

20. informal

    1. to lose one's temper (with a person)

       she really let fly at him

    2. to shoot or throw (an object)

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noun

1. Also called: fly front.  (often plural) a closure that conceals a zip, buttons, or other fastening, by having one side overlapping, as on trousers

2. Also called: fly sheet. 

   1. a flap forming the entrance to a tent

   2. a piece of canvas drawn over the ridgepole of a tent to form an outer roof

3. a small air brake used to control the chiming of large clocks

4. the horizontal weighted arm of a fly press

5. 1. the outer edge of a flag

   2. the distance from the outer edge of a flag to the staff Compare hoist

6. a light one-horse covered carriage formerly let out on hire

7. an attempt

   I'll give it a fly

8. printing

   1. a device for transferring printed sheets from the press to a flat pile

   2. Also called: flyhand.  a person who collects and stacks printed matter from a printing press

   3. a piece of paper folded once to make four pages, with printing only on the first page

9. (plural) theatre the space above the stage out of view of the audience, used for storing scenery, etc

10. rare the act of flying

fly Scientific  

/ flī /

1. Any of numerous insects of the order Diptera, having one pair of wings and large compound eyes. Flies include the houseflies, horseflies, and mosquitoes.

2. See more at dipteran

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Usage

Plural word for fly The plural form of fly is flies. Words that end with a -y and are preceded by a consonant are made plural by changing the -y to -ies, as in party/parties, candy/candies, and duty/duties.  This can be confusing, because words that end with a -y and are preceded by a vowel (a, e, i, o, u) are pluralized by adding an -s to the end, as in chimney/chimneys and fray/frays.

Synonym Usage

Fly, flit, flutter, hover, soar refer to moving through the air as on wings. Fly is the general term: Birds fly. Airplanes fly. To flit is to make short rapid flights from place to place: A bird flits from tree to tree. To flutter is to agitate the wings tremulously, either without flying or in flying only short distances: A young bird flutters out of a nest and in again. To hover is to linger in the air, or to move over or about something within a narrow area or space: hovering clouds; a hummingbird hovering over a blossom. To soar is to (start to) fly upward to a great height usually with little advance in any other direction, or else to (continue to) fly at a lofty height without visible movement of the wings: Above our heads an eagle was soaring.

Other Word Forms

Derived Forms

• flyability
  noun
• flyable
  adjective
• flyless
  adjective
• nonflyable
  adjective
• reflyable
  adjective
• unflyable
  adjective

Inflected Forms

Nouns

• flies
  plural

Participles

• flying
  present
• flied
  past
• flown
  past

Conjugated Forms

Present

• fly
  simple
• flies
  simple
• have flied
  perfect
• have flown
  perfect
• has flied
  perfect
• has flown
  perfect
• am flying
  progressive
• are flying
  progressive
• is flying
  progressive
• have been flying
  perfect progressive
• has been flying
  perfect progressive

Past

• flew
  simple
• flied
  simple
• had flied
  perfect
• had flown
  perfect
• was flying
  progressive
• were flying
  progressive
• had been flying
  perfect progressive

Future

• will fly
  simple
• will have flied
  perfect
• will have flown
  perfect
• will be flying
  progressive
• will have been flying
  perfect progressive

Etymology

Origin of fly¹

First recorded before 950; Middle English flīe, Old English flēoge, flȳge; cognate with Middle Dutch vliege ( Dutch vlieg ), Old High German flioga ( German Fliege ); akin to fly ²

Origin of fly²

First recorded before 900; Middle English flīen, Old English flēogan; cognate with Old High German fliogan, German fliegen, Old Norse fljuga

Origin of fly³

First recorded in 1805–15; perhaps special use of fly ²

Explanation

Fly describes moving through the air, like birds that fly in the sky, or getting something accepted, like your silly excuse that's not going to fly with your history teacher. Fly means "move through the air with wings," and it describes the movement of birds, airplanes, kites, and other things that float or move of their own accord above the ground. There are many other meanings of fly, including a buzzing insect with wings, a baseball hit high across a field, and the zipper on a pair of pants. As an adjective, fly means cool, though there's no guarantee it's still fly to use it.

Example Sentences

See Examples For:

fly flies flyer flyest flew flied flown flying

Video of the maneuver, which went viral on social media, shows an F/A-18 Super Hornet fly low over the beach before turning over the water and climbing to a higher altitude.

From The Wall Street Journal ● Jul. 16, 2026

But in fairness to the state party, which had to create this process on the fly, Platner’s implosion left no good options.

From Slate ● Jul. 16, 2026

When Russian tanks rolled toward his capital and the U.S. offered to fly him to safety and exile, he stayed, and he answered: I need ammunition, not a ride.

From Salon ● Jul. 15, 2026

Behind-closed-doors friendlies against Crawley Town on Saturday and Bromley next Thursday, before they fly for their overseas pre-season tour next Friday.

From BBC ● Jul. 14, 2026

Mal was forbidden to fly anywhere except around the garden or across the fields: her great-aunt Leonor would have been horrified had she known how far Mal went.

From "Impossible Creatures" by Katherine Rundell

“Time flies, you know?” he says, smiling, of visiting Likho over the years.

From Los Angeles Times ● Jul. 17, 2026

Residents, they said, were fed up with exposure to toxic smoke, the smell of rotting food, swarms of flies and other vermin.

From Los Angeles Times ● Jul. 14, 2026

He’s made a fortune, flies private, stays in fancy schmancy lairs, all the Lacoste he can wear.

From The Wall Street Journal ● Jul. 11, 2026

The new offer signalled the start of a bidding war for the carrier that flies mainly across Europe.

From Barron's ● Jul. 10, 2026

He rubbed his belly and said June bugs had more flavor and crunch than flies.

From "The Seven Wonders of Sassafras Springs" by Betty G. Birney

A flyer featuring a pink background was the top Instagram post on California state superintendent candidate Sonja Shaw’s page on Saturday morning.

From Los Angeles Times ● May 14, 2026

By early February of that year, the company was days away from announcing its new plan to car dealers, including a fax-based marketing plan and promotional flyer, ready for final approval.

From Salon ● Mar. 30, 2026

The bloc lets diplomats rack up frequent flyer miles, and politicians pose for pictures with other leaders.

From The Wall Street Journal ● Mar. 11, 2026

Now, all it takes is for a content page to drop a flyer and poof: a crowd that can swallow the park whole.

From Slate ● Feb. 28, 2026

I look at her and she’s twisting up a flyer someone was handing out about some student council fundraiser.

From "The Benefits of Being an Octopus" by Ann Braden

“If you have an outfit on, but you don’t have cologne on or you don’t smell good, do you even have the flyest fit on? What’s the point,” he says.

From Los Angeles Times ● May 28, 2024

She told her fellow graduates and their families that they were “the flyest class ever to do it.”

From Seattle Times ● Jul. 15, 2023

Unlike her fellow Jersey teens who insist that superheroes aren’t cool, Kamala Khan, the heroine of Marvel’s upcoming Ms. Marvel series, thinks capes are the flyest thing in the world.

From The Verge ● Mar. 15, 2022

The coolest, the flyest, and the funniest dudes are all gone.

From Salon ● Apr. 23, 2019

How do you not know one of the flyest runners to ever take a lap?

From "Patina" by Jason Reynolds

When I flew, I found that I hardly waited more than five minutes in the regular airport security line, anyway.

From MarketWatch ● Jul. 14, 2026

Dan Tana flew back to Los Angeles, expecting charred remains.

From Los Angeles Times ● Jul. 14, 2026

Ederson flew to England for the required tests, which took place in the wake of Brazil's last-16 defeat by Norway.

From BBC ● Jul. 13, 2026

Though she was undergoing cancer treatment, Gillison flew to Vietnam last December with her family to receive a VinFuture prize from a foundation founded by Pham Nhat Vuong, a Vietnamese billionaire.

From The Wall Street Journal ● Jul. 10, 2026

All the air was knocked out of me and sparks flew in my eyes, but I had to run because the maid’s bellowing was sure to bring the guards after me any moment.

From "Rump: The (Fairly) True Story of Rumpelstilskin" by Liesl Shurtliff

That cut the Guardians’ lead to three runs before Will Smith flied out to deep center to end it.

From Los Angeles Times ● Apr. 1, 2026

Freeman, however, flied out to leave more baserunners stranded.

From Los Angeles Times ● Sep. 3, 2025

Lindor flied out to center and Mark Vientos struck out to end the inning.

From Los Angeles Times ● Oct. 13, 2024

On Tuesday, Ohtani struck out twice, flied out and had a broken-bat single.

From Los Angeles Times ● Oct. 9, 2024

Thurlow flied out to pitcher, Pryor sacrificed and Bacon reached second.

From The Crimson Sweater by Barbour, Ralph Henry

Nearly 11 million U.S. citizens have flown to Europe between January and June, up 2.2% compared to the same period last year, according to International Trade Administration data.

From The Wall Street Journal ● Jul. 12, 2026

Kites in the black, white, green and red of the Palestinian flag soar overhead, joined by another in the colours of Egypt, flown in tribute to the Egyptian national football team.

From Barron's ● Jul. 11, 2026

Spain have every chance of beating France, even if they have flown slightly under the radar at this World Cup.

From BBC ● Jul. 9, 2026

He was flown to another hospital where he recovered and has since been released.

From BBC ● Jul. 8, 2026

During his first days at Mount St. Helens, Swanson had flown to Goat Rocks and Sugar Bowl, another feature on the mountain about fifteen hundred feet below Goat Rocks.

From "Mountain of Fire" by Rebecca E. F. Barone

But however they look and whatever they cost, ranch bottles are flying off shelves right now.

From The Wall Street Journal ● Jul. 17, 2026

Yet here I was, without him, flying high on the joy of grandparenting.

From Los Angeles Times ● Jul. 17, 2026

UK holidaymakers are flying out on summer holidays in their thousands, but some will face disruption to their flights.

From BBC ● Jul. 15, 2026

The company “made the space economy an investible category,” he told MarketWatch, when it began flying the Falcon 9 rocket.

From MarketWatch ● Jul. 15, 2026

Bits of flying debris slammed into their Gore-Tex rain suits like shotgun pellets.

From "Storm Runners" by Roland Smith

Related Words

• circle
• climb
• cross
• drift
• float
• flutter
• glide
• operate
• pilot
• reach
• rush
• sail
• shoot
• speed
• swoop
• take off
• travel