\ ˈflī How to pronounce fly (audio) \
flew\ ˈflü How to pronounce flew (audio) \; flown\ ˈflōn How to pronounce flown (audio) \; flying

Definition of fly

 (Entry 1 of 6)

intransitive verb

1a : to move in or pass through the air with wings bees flying around the hive
b : to move through the air or before the wind or through outer space bullets flying in all directions
c : to float, wave, or soar in the air flags flying at half-mast
2a : to take flight : flee was forced to fly for his life when his enemies came into power
b : to fade and disappear : vanish mists flying before the morning sun
3a : to move, pass, or spread quickly rumors were flying
b : to be moved with sudden extreme emotion flew into a rage
c : to seem to pass quickly the time simply flew
4 : to become expended or dissipated rapidly After he became established in the town, his inheritance flew.
5 : to operate or travel in an airplane or spacecraft They flew to Florida for their vacation.
6 : to work successfully : win popular acceptance knew … a pure human-rights approach would not fly— Charles Brydon

transitive verb

1a : to cause to fly, float, or hang in the air flying a kite
b : to operate (something, such as a balloon, aircraft, rocket, or spacecraft) in flight
c : to journey over or through by flying flew the Atlantic
2a : to flee or escape from The bird had flown its cage.
b : avoid, shun fly such a talkative woman
3 : to transport by aircraft or spacecraft Supplies were flown to the disaster area.
fly at
: to assail suddenly and violently He flew at me in a rage.
fly blind
: to fly an airplane solely by instruments
fly high
: to be elated She was flying high after winning the contest.
fly in the face of or fly in the teeth of
: to stand or act forthrightly or brazenly in defiance or contradiction of His explanation flies in the face of the evidence.
plural flies

Definition of fly (Entry 2 of 6)

1 : the action or process of flying : flight
2a : a device consisting of two or more radial vanes capable of rotating on a spindle to act as a fan or to govern the speed of clockwork or very light machinery
3 flies plural : the space over a theater stage where scenery and equipment can be hung
4 : something attached by one edge: such as
a : a garment closing concealed by a fold of cloth extending over the fastener
b(1) : the length of an extended flag from its staff or support
(2) : the outer or loose end of a flag
5 : a baseball hit high into the air
7 : a sheet of material (such as canvas) that is attachable to a tent for use as a double top or as a rooflike extension
8 : a football pass pattern in which the receiver runs straight downfield
on the fly
1 : in motion : busy
2 : while still in the air : without the ball bouncing the home run carried 450 feet on the fly
3 : in a hurry and often without preparation : hastily, spontaneously making decisions on the fly
4 : simultaneously with another task software that handles formatting on the fly
flied; flying

Definition of fly (Entry 3 of 6)

intransitive verb

: to hit a fly in baseball
plural flies

Definition of fly (Entry 4 of 6)

1 : a winged insect usually used in combinationmayfliesbutterfly
2a : any of a large order (Diptera) of winged or rarely wingless insects (such as the housefly, mosquito, or gnat) that have the anterior wings functional, the posterior wings reduced to halteres, and segmented often headless, eyeless, and legless larvae — compare maggot
b : a large stout-bodied fly
3 : a fishhook dressed (as with feathers or tinsel) to suggest an insect
fly in the ointment
: a detracting factor or element

Definition of fly (Entry 5 of 6)

chiefly British


geographical name
\ ˈflī How to pronounce Fly (audio) \

Definition of Fly (Entry 6 of 6)

river 650 miles (1046 kilometers) long in southern New Guinea flowing southeast into the Gulf of Papua

Synonyms for fly

Synonyms: Verb (1)

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First Known Use of fly

Verb (1)

before the 12th century, in the meaning defined at intransitive sense 1a

Noun (1)

before the 12th century, in the meaning defined at sense 1

Verb (2)

1893, in the meaning defined above

Noun (2)

before the 12th century, in the meaning defined at sense 1


1811, in the meaning defined above

History and Etymology for fly

Verb (1) and Noun (1)

Middle English flien, from Old English flēogan; akin to Old High German fliogan to fly and probably to Old English flōwan to flow

Noun (2)

Middle English flie, from Old English flēoge; akin to Old High German flioga fly, Old English flēogan to fly


probably from fly entry 1

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Time Traveler for fly

Time Traveler

The first known use of fly was before the 12th century

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Statistics for fly

Cite this Entry

“Fly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fly. Accessed 1 Oct. 2020.

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More Definitions for fly


\ ˈflī How to pronounce fly (audio) \
flew\ ˈflü \; flown\ ˈflōn \; flying

Kids Definition of fly

 (Entry 1 of 3)

1 : to move in or pass through the air with wings Birds and airplanes fly.
2 : to move through the air or before the wind Paper was flying in all directions.
3 : to float or cause to float, wave, or soar in the wind fly a kite fly a flag
4 : to run away : flee … calling out to him to fly, for God's sake, by the window …— Charles Dickens, The Cricket on the Hearth
5 : to pass or move swiftly Time flies. Cars were flying past us.
6 : to operate or travel in an aircraft fly a jet I'm flying home for the holidays.
7 : to become suddenly emotional He flew into a rage.


plural flies

Kids Definition of fly (Entry 2 of 3)

1 : a flap of material to cover a fastening in a garment
2 : a layer of fabric that goes over the top of a tent
3 : a baseball hit very high


plural flies

Kids Definition of fly (Entry 3 of 3)

1 : any of a large group of mostly stout-bodied two-winged insects (as the housefly)
2 : a winged insect
Hint: This sense of fly is usually used in combination. dragonfly firefly
3 : a fishhook made to look like an insect


\ ˈflī How to pronounce fly (audio) \
plural flies

Medical Definition of fly

1 : a winged insect usually used in combination emerging mayflies a large butterfly
2a : any dipteran fly

called also true fly, two-winged fly

b : a large and stout-bodied dipteran fly (as a horsefly)

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