fly

plural flies

1. biologyAny insect of the order Diptera; characterized by having two wings (except for some wingless species), also called true flies.

   Devils Lake is where I began my career as a limnologist in 1964, studying the lake’s neotenic salamanders and chironomids, or midge flies. […] The Devils Lake Basin is an endorheic, or closed, basin covering about 9,800 square kilometers in northeastern North Dakota.

   2012 January 28, Douglas Larson, “Runaway Devils Lake”, in American Scientist, volume 100, number 1, page 46

2. non-technicalEspecially, any of the insects of the family Muscidae, such as the common housefly (other families of Diptera include mosquitoes and midges).

   When you're well enough off so's you don't have to fret about anything but your heft or your diseases you begin to get queer, I suppose. And the queerer the cure for those ailings the bigger the attraction. A place like the Right Livers' Rest was bound to draw freaks, same as molasses draws flies.

   1913, Joseph C[rosby] Lincoln, chapter V, in Mr. Pratt’s Patients, New York, N.Y.; London: D[aniel] Appleton and Company, →OCLC

   1 more example

   October in Orania can be charming. When the sun sets, long ribbons of burnt orange settle on the horizon. The flies and mosquitoes that come with the oppressive summer heat haven’t arrived yet. It is Magdalene Kleynhans’ favourite time of year. “You can sit outside until late into the night,” says the businesswoman, whose family spend much of their time outdoors. Her children fish from the banks of the Orange River whenever they choose. Kleynhans leaves the house unlocked. “It’s a good life. It’s a big privilege.”

   2019 October 24, Dennis Webster, “'An indictment of South Africa': whites-only town Orania is booming”, in The Guardian, archived from the original on 29 Mar 2022

3. Those or any similar but not closely related insect, such as a dragonfly, butterfly, or gallfly.
4. fishingA lightweight fishing lure resembling an insect.

   I went on trying for fish along the western bank down the river, but only small trout rose at my flies, and a score was the total catch.

   1886, Peter Christen Asbjø￵rnsen, translated by H.L. Brækstad, Folk and Fairy Tales, page 152

5. hobbiesA chest exercise performed by moving extended arms from the sides to in front of the chest. (also flye)
6. hobbiesThe butterfly stroke (plural is normally flys).
7. obsoleteA witch's familiar.

   a trifling fly, none of your great familiars

   1610 (first performance), Ben[jamin] Jonson, The Alchemist, London: […] Thomas Snodham, for Walter Burre, and are to be sold by Iohn Stepneth, […], published 1612, →OCLC, (please specify the Internet Archive page), (please specify the scene number in lowercase Roman numerals)

8. obsoleteA parasite.

   The fly that plays too near the flame burns in it.

   1636, Philip Massinger, “The Bashful Lover”, in William Gifford, editor, The Plays of Philip Massinger, published 1845, act 1, scene 1, page 470

9. preceded by definite articleA simple dance in which the hands are shaken in the air, popular in the 1960s.
10. businessA butterfly (combination of four options).

present singular third person flies · participle present flying · past flew · participle past flown · first person past singular flew · archaic present second person singular fliest · archaic present second person singular flyest · past second person singular flew · archaic past second person singular flewest · present singular third person flies · archaic present singular third person flieth · archaic present singular third person flyeth · past singular third person flew · past plural flew · past subjunctive flew · participle present flying

1. intransitiveTo travel through the air, another gas, or a vacuum, without being in contact with a grounded surface.

   The probe flew beyond the solar system.

   5 more examples

   Birds of passage fly to warmer regions as it gets colder in winter.

   The Concorde flew from Paris to New York faster than any other passenger airplane.

   It takes about eleven hours to fly from Frankfurt to Hong Kong.

   The little fairy flew home on the back of her friend, the giant eagle.

   Angels can fly because they take themselves lightly.

   1909, Gilbert Keith Chesterton, Orthodoxy

   Synonyms: ascend, aviate, float, flutter, glide, hover, rise, skim

   1. intransitiveTo take a flight on a plane; to pilot or crew a plane.

      My airline needs me to get clearance before I can fly again.

      1 more example

      If we want to fly today, we need to leave for the airport right now.

      Synonyms: ascend, aviate, float, flutter, glide, hover, rise, skim

   2. intransitivebiologyTo be in the winged adult stage.

      This species flies from late summer until frost.

      Synonyms: ascend, aviate, float, flutter, glide, hover, rise, skim

   3. colloquialfigurativelyintransitiveproject or ideaTo be accepted, come about or work out.

      Let's see if that idea flies.

      1 more example

      You know, I just don't think that's going to fly. Why don't you spend your time on something better?

      Synonyms: ascend, aviate, float, flutter, glide, hover, rise, skim

2. transitiveTo cause to fly (travel or float in the air): to transport via air or the like.

   Birds fly their prey to their nest to feed it to their young.

   5 more examples

   Charles Lindbergh flew his airplane The Spirit of St. Louis across the Atlantic ocean.

   Each day the postal service flies thousands of letters around the globe.

   The brave black flag I fly.

   1879, W[illiam] S[chwenck] Gilbert, Arthur Sullivan, composer, The Pirates of Penzance […], Philadelphia: J.M. Stoddart & Co., published 1880, →OCLC

   A solar-powered unmanned aerial system (a UAS, more commonly called a drone) could fly long, lonely missions that conventional aircraft would not be capable of.

   2013 September 7, “On a bright new wing”, in The Economist, volume 408, number 8852

   This area, referred to as the fly loft, should typically be two and a half times taller than the proscenium opening in order to fly the scenery above the vertical sightlines of the first row of the audience.

   2015, Jeromy Hopgood, Dance Production: Design and Technology, page 44

   1. transitiveTo arrange for someone to take a flight.

      We flew the kids out to see their grandparents.

   2. transitiveTo pilot a plane over a region or on a route.

      This is the first time I flew the Pacific.

      1 more example

      I'm hoping to fly the London-New York route so I can see the Big Apple again.

   3. transitiveTo complete (a goal, task, mission, etc.) while crewing an aircraft or spacecraft.

      NASA astronaut Mike Fincke is departing the agency on Wednesday after 30 years of service. Throughout his career, he flew four missions, spent 549 days in space, and completed nine spacewalks in support of the International Space Station.

      2026 August 12, Lauren E. Low, “NASA Astronaut Mike Fincke Leaves NASA, Career Includes 4 Spaceflights”, in NASA, archived from the original on 13 Aug 2026

   4. transitiveTo hunt with a hawk.

      We'll fly the partridge, or go rouse the deer.

      c. 1590, Robert Greene, Friar Bacon and Friar Bungay

3. ergativeTo wave or flutter; to cause to wave or flutter.

   When the wind picked up, her hair flew back behind her head.

   1 more example

   In her dance, she holds her hands above her head to fly those colorful ribbons in the air.

   1. ergativeTo operate a kite (A lightweight toy or other device... carried on the wind and tethered and controlled from the ground by one or more lines).

      Why don’t you go outside and fly kites, kids? The wind is just perfect.

   2. ergativeTo display (a flag) on a flagpole; to be displayed on a flagpole.

      The flag flew at half-mast.

      2 more examples

      We flew the state flag under the national flag.

      The American flag flies in every state and territory.

   3. ergativefigurativelytransitiveTo proudly and openly make one's allegiances or viewpoint apparent.

      She's really letting the freak flag fly.

      3 more examples

      What she realized, in short, is she could go with her funk and quirk, be who she was and fly the freak flag high and be herself and not fall back into, well, toaster mode.

      2002 July 3, Mark Morford, “Girl With The Toaster Tattoo”, in San Francisco Chronicle, archived from the original on 21 Mar 2012

      Halloween is a great day to be dead. Or, technically speaking, undead. A vampire like me can be just a bit more herself in public, fly the freak flag a few feet higher.

      2012, Jeri Smith-Ready, Lust for Life, Simon and Schuster, →ISBN, page 1

      Only one candidate is willing to fly the conservative flag boldly.

   4. ergativefigurativelyTo symbolically rule over or control.

      The French flag flew over Louisiana until 1803.

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      The king endeavored to fly his nation's flag over new territories.

4. intransitiveTo drain away or be expended quickly.

   The family fortune flew in a few short years.

   1. datedintransitiveTo vanish; to fade away.

      The mist flew by noon.

      Synonyms: dissipate

5. figurativelyintransitiveTo travel or proceed very fast; to hasten.

   He flew down the hill on his bicycle.

   4 more examples

   It's five o'clock already. Doesn't time fly?

   Fly, envious Time, till thou run out thy race.

   1645, John Milton, On Time

   The dark waves murmured as the ship flew on.

   1870, William Cullen Bryant (translator), The Iliad (originally by Homer)

   After yet another missed penalty by Kvirikashvili from bang in front of the posts, England scored again, centre Tuilagi flying into the line and touching down under the bar.

   2011 September 18, Ben Dirs, “Rugby World Cup 2011: England 41-10 Georgia”, in BBC Sport

   Synonyms: dart, flit, speed

   1. figurativelyintransitiveTo move suddenly, or with violence; to carry out an act suddenly or swiftly.

      a door flies open

      3 more examples

      a bomb flies apart

      And in respect of the great necessity there is, my darling, for more employments being within the reach of Woman than our civilisation has as yet assigned to her, don’t fly at the unfortunate men, even those men who are at first sight in your way, as if they were the natural oppressors of your sex […]

      1859 December 13, Charles Dickens, “The Mortals in the House”, in Charles Dickens, editor, The Haunted House. The Extra Christmas Number of All the Year Round […], volume II, London: […] C[harles] Whiting, […], →OCLC, page 7, column 1

      I was upstairs, trying hastily to fix my face and unredden my eyes when I heard a car on the drive and flew to a window to make sure that it was David.

      1976, J. P. Reading, chapter 15, in Tanya, New York, N.Y.: Scholastic Book Services, →OCLC, page 174

      Synonyms: dart, flit, speed, hurry, zoom

   2. figurativelyintransitiveTo proceed with great success.

      His career is really flying at the moment.

      1 more example

      One moment the company was flying high, the next it was on its knees.

      Synonyms: dart, flit, speed

   3. archaicfigurativelyintransitiveliterarytransitiveTo avoid or shun.

      I must fly the temptation of drink.

      Synonyms: dart, flit, speed

   4. ambitransitivearchaicfigurativelyintransitivepoeticTo flee, to escape (from).

      My bird flew the cage.

      5 more examples

      Fly, my lord! The enemy are upon us!

      [V]pon a ſodaine, / As Falſtaffe, ſhe, and I, are newly met, / Let them [children dressed like "urchins, ouphes and fairies"] from forth a ſaw-pit ruſh at once / With ſome diffuſed ſong: Vpon their ſight / We two, in great amazedneſſe will flye: […]

      c. 1597 (date written), William Shakespeare, “The Merry Wiues of Windsor”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act IV, scene iv], page 56, column 1

      to fly the favours of so good a king

      c. 1604–1605 (date written), William Shakespeare, “All’s Well, that Ends Well”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act III, scene ii]

      Fly, ere evil intercept thy flight.

      1667, John Milton, “Book V”, in Paradise Lost. […], London: […] [Samuel Simmons], and are to be sold by Peter Parker […]; [a]nd by Robert Boulter […]; [a]nd Matthias Walker, […], →OCLC; republished as Paradise Lost in Ten Books: […], London: Basil Montagu Pickering […], 1873, →OCLC

      Sleep flies the wretch.

      1693, Decimus Junius Juvenalis, John Dryden, transl., “[The Satires of Decimus Junius Juvenalis.] The Fourteenth Satyr”, in The Satires of Decimus Junius Juvenalis. Translated into English Verse. […] Together with the Satires of Aulus Persius Flaccus. […], London: […] Jacob Tonson […], →OCLC

      Synonyms: dart, flit, speed, abscond, escape, flee · Antonyms: remain, stay

plural flys · plural flies

1. obsoleteThe action of flying; flight.
2. An act of flying.

   There was a good wind, so I decided to give the kite a fly.

3. ball gamesA fly ball.
4. abbreviationellipsisAmerican footballEllipsis of fly route.
5. A piece of canvas that covers the opening at the front of a tent.
6. IndiaobsoleteThe sloping or roof part of the canvas of a tent.

   After I had changed my riding-habit for my one other gown, I came out to join the general under the tent-fly.

   1885, Elizabeth Bacon Custer, Boots and Saddles

   2 more examples

   [T]he main part of the operation of pitching the tent, consisting of raising the flies, may be performed, and shelter afforded, without the walls, &c., being present.

   1810, Thomas H. Williamson, The East India Vade-Mecum, page 452

   The cavalcade drew up in line, / Pitch'd the marquee, and went to dine. / The bearers and the servants lie / Under the shelter of the fly.

   1816, The Grand Master, or Adventures of Qui Hi, page 152

7. often in the plural with the same meaningA strip of material (sometimes hiding zippers or buttons) at the front of a pair of trousers, pants, underpants, bootees, etc.

   your fly's undone/down

   4 more examples

   Ha-ha! Your fly's undone!

   your flies are undone/down (same meaning)

   February 2014 Y-Front Fly Y-Front is a registered trademark for a special front fly turned upside down to form a Y owned by Jockey® International. The first Y-Front® brief was created by Jockey® more than 70 years ago.

   June 2014 The Hole In Men’s Underwear: Name And Purpose Briefs were given an opening in the front. The point of this opening (the ‘fly’) was to make it easier to pee with clothes on

8. The moving portion of an extendable ladder.
9. historyThe free edge of a flag.
10. historyThe horizontal length of a flag.
11. hobbiesAn exercise that involves wide opening and closing of the arms perpendicular to the shoulders.
12. The part of a weather vane pointing the direction from which the wind blows.
13. nauticalThat part of a compass on which the points are marked; the compass card.

    to the fly of the compass, which before was made equal, I was still constrained to put some small piece of wire on the south part there

    a. 1850, Robert Norman, (Please provide the book title or journal name)

14. Two or more vanes set on a revolving axis, to act as a fanner, or to equalize or impede the motion of machinery by the resistance of the air, as in the striking part of a clock.
15. abbreviationellipsisEllipsis of flywheel.
16. historicalA type of small, light, fast horse-drawn carriage that can be hired for transportation (sometimes pluralised flys).

    A fly carried him rapidly to Lady Clavering’s house from the station […]

    1848 November – 1850 December, William Makepeace Thackeray, chapter 74, in The History of Pendennis. […], volume (please specify |volume=I or II), London: Bradbury and Evans, […], published 1849–1850, →OCLC

    5 more examples

    Can I get a fly, or a carriage of any kind? Is it too late? I dismissed the fly a mile distant from the park, and getting my directions from the driver, proceeded by myself to the house.

    1859, Wilkie Collins, The Woman in White

    A glass coach, it may be as well to observe, is a carriage and pair hired by the day, and a fly a one-horse carriage hired in a similar manner.

    1861, Henry Mayhew, William Tuckniss, London Labour and the London Poor: A Cyclopœdia of the Condition and Earnings of Those that Will Work, Those that Cannot Work, and Those that Will Not Work, volume 3, page 359

    As we left the house in my fly, which had been waiting, Van Helsing said:— ‘Tonight I can sleep in peace [...].’

    1897, Bram Stoker, Dracula, Westminster [London]: Archibald Constable and Company, […], →OCLC

    “[…] She takes the whole thing with desperate seriousness. But the others are all easy and jovial—thinking about the good fare that is soon to be eaten, about the hired fly, about anything.”

    1918, W[illiam] B[abington] Maxwell, chapter XVI, in The Mirror and the Lamp, Indianapolis, Ind.: The Bobbs-Merrill Company, →OCLC

    And, driving back in the fly, Macmaster said to himself that you couldn't call Mrs. Duchemin ordinary, at least.

    1924, Ford Madox Ford, Some Do Not… (Parade's End), Penguin, published 2012, page 54

17. In a knitting machine, the piece hinged to the needle, which holds the engaged loop in position while the needle is penetrating another loop; a latch.
18. The pair of arms revolving around the bobbin, in a spinning wheel or spinning frame, to twist the yarn.
19. businessA shuttle driven through the shed by a blow or jerk.
20. historicalmediaThe person who took the printed sheets from the press.
21. historicalmediaA vibrating frame with fingers, attached to a power printing press for doing the same work.
22. One of the upper screens of a stage in a theatre.

    1 more example

    It was as if I been idling on a brightly lit stage-set of a country garden, ripe with every sort of pastoral fancy, and then had turned a flat and come on the stagehands and the wings, the propped sets, the men working in the flies—all the dark mechanics that produced the pretty picture the audience saw.

    2006, Alistair Cooke, The American Home Front, 1941-1942, page 128

23. cotton manufactureWaste cotton.

present singular third person flies · participle present flying · participle past flied · past flied · participle past flyed · past flyed

1. intransitiveball gamesTo hit a fly ball; to hit a fly ball that is caught for an out. Compare ground (verb) and line (verb).

   Jones flied to right in his last at-bat.

comparative flier · comparative flyer · superlative fliest · superlative flyest

1. datedslangQuick-witted, alert, mentally sharp.

   1 more example

   be assured, O man of sin—pilferer of small wares and petty larcener—that there is an eye within keenly glancing from some loophole contrived between accordions and tin breastplates that watches your every movement, and is "fly,"— to use a term peculiarly comprehensible to dishonest minds—to the slightest gesture of illegal conveyancing.

   1854, Charles Dickens, “Household Words”, in Arcadia, volume 7, page 381

2. slangClandestine, surreptitious

   Some say God was an alien that tampered with our DNA, the 3 kings followed ufos & Mary had a fly shag 🤔🤫

   2023 December 1, @Davo_Mack, Twitter

3. slangWell dressed, smart in appearance; in style, cool.

   He's pretty fly.

   5 more examples

   when Ortega got fixed up in his fly duds like that, an ord'nary man's overcoat wouldn't make 'im a pair o' socks.

   1888, Frederick Thickstun Clark, A Mexican Girl, page 270

   Give it to me, baby! Uh huh, uh huh! And all the girlies say, I’m pretty fly for a white guy.

   1998, “Pretty Fly (For a White Guy)”performed by The Offspring

   Starring the light-skinned Ron O'Neal with his shoulder-length perm and fly threads, Super Fly exudes a sense of black pride as O'Neal bucks the dope game, dismisses his white girlfriend, and beats The Man at his own hustle.

   2001 September 28, “Super Fly”, in Vibe, volume 9, number 9, page 252

   A fly sister rolled in with a suitcase full of hip-hop novels called The Glamorous Life, and an African brother with long dreads wanted to sell them some incense and some fake Jacob watches.

   2006, Noire [pseudonym], Thug-A-Licious: An Urban Erotic Tale, New York, N.Y.: One World, Ballantine Books, →ISBN, page 169

   How NOT to Facebook / […] no naked pictures, no deep emotions (awkward), no tagging a bunch of people in a picture of some fly Nikes, no making dinner plans (just use a PHONE).

   2012, Lindy West, Dan Savage, Christopher Frizzelle, How to Be a Person: The Stranger's Guide to College, Sex, Intoxicants, Tacos, and Life Itself

4. slangBeautiful; displaying physical beauty.

   I rap for listeners, blunt heads, fly ladies and prisoners

   1994, “Memory Lane (Sittin’ in da Park)”, in Illmatic, performed by Nas

   2 more examples

   [Rahiem] My name brings peace and tranquility / So all the fly ladies' hearts can run free

   1979, “We Rap More Mellow”, performed by The Younger Generation

   Word is bond she looked divine, she looked as fly as can be I thought she was different cause she was by herself She looked real wholesome, and in good physical health

   1991, “Busy Doin Nuthin”, in I Need a Haircut, performed by Biz Markie

plural flies

1. Northern EnglandScotlandrusticA wing.

   The bullet barely grazed the wild fowl's fly.

plural flies

1. alternativeAlternative form of vly (“swamp (in New York)”).

   […] to a white maple stake standing in a fly or swamp , thence N [...] to a Hemlock Stake, […]

   1961, William Gideon Closson, The Josiah Closson Family of New England, page 110

   2 more examples

   June 8, 1708, John Cock and William Nottingham desire 100 acres each [...] Isaac Davis desied a conveyance for the "greenbush" fly or swamp that he hath drained near his land, in the Jaagh Creupel-bosh.

   1880, Nathaniel Bartlett Sylvester, History of Ulster County, New York: With Illustrations and..., page 185

   […] one certain Lot of the Long fly, or swamp situate lying and being [in] the Township of Flatlands […] recorded June 15, 1876, Liber 1244 of Conveyances, at page 494, Kings County. The "East Division" was the Long Vly, […]

   1924, Frederick Van Wyck, Keskachauge: Or the First White Settlement on Long Island, page 321

1. A river in Papua New Guinea

plural Flys

1. A surname.