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Synonyms

fly

1 American  
[flahy] / flaɪ /

noun

PLURAL

flies
  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.


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)

flew, flied flown flying
  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.


verb (used with object)

flying flew, flied flown
  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

PLURAL

flies
  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 fanHorology.  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 loftTheater.  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.


fly 1 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

    1. to procure money by an accommodation bill

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

  14. informal

    1. to have a high aim

    2. to prosper or flourish

  15. See face

  16. informal  to lose one's temper

  17. informal  to leave suddenly

  18. informal  go away

  19. informal

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

      she really let fly at him

    2. to shoot or throw (an object)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

    1. the outer edge of a flag

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

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

  6. an attempt

    I'll give it a fly

  7. 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

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

  9. rare  the act of flying

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

fly 3 British  
/ flaɪ /

adjective

  1. knowing and sharp; smart

  2. furtive or sneaky

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. in secret; sneakily

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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


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.

Related Words

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

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

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 fly1

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

Origin of fly1

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In 2020 the Japanese Aerospace eXploration Agency sent out Hayabusa2 to learn more about the smallest of asteroids flying around in our Solar System and bring back some samples.

From Space Scoop

Eventually, Truell and the team grew more aggressive about hiring, flying around the world to persuade people to join them, even if they had previously said no.

From The Wall Street Journal

Government authorities have stepped in with official relief measures and sanctioned mourning activities, such as flying flags at half-staff and the establishment of designated condolence sites.

From The Wall Street Journal

Bodies collide in a whirl of elbows and flying sneakers.

From Los Angeles Times

Hughes is the most famous bridge between film and flight — producing movies and later running RKO Pictures while also founding Hughes Aircraft Co., building and flying game-changing planes and, eventually, running Trans World Airlines.

From Los Angeles Times