\ ˈflash \
flashed; flashing; flashes

Definition of flash 

(Entry 1 of 4)

intransitive verb

1 : rush, dash used of flowing water

2 : to break forth in or like a sudden flame or flare

3a : to appear suddenly an idea flashes into her mind

b : to move with great speed the days flash by

4a : to break forth or out so as to make a sudden display

b : to act or speak vehemently and suddenly especially in anger

5a : to give off light suddenly or in transient bursts

b : to glow or gleam especially with animation or passion her eyes flashed with anger

6 : to change suddenly or violently into vapor

7 : to expose one's breasts or genitals usually suddenly and briefly in public

8 : to have sudden insight often used with on

transitive verb

1a archaic : splash

b : to fill by a sudden inflow of water

2a : to cause the sudden appearance of (light)

b : to cause to burst violently into flame

c(1) : to cause (light) to reflect

(2) : to cause (something) to reflect light flash a mirror

(3) : to cause (a lamp) to flash

d : to convey by means of flashes of light

3a : to make known or cause to appear with great speed flash a message on the screen

b : to display obtrusively and ostentatiously always flashing a roll of bills

c : to expose to view usually suddenly and briefly flashed a badge

4 : to cover with or form into a thin layer: such as

a : to protect against rain by covering with sheet metal or a substitute

b : to coat (glass) with a thin layer (as of metal or a differently colored glass)

5 : to subject (an exposed photographic negative or positive) to a supplementary uniform exposure to light before development in order to modify detail or tone

6 : to expose one's breasts or genitals usually suddenly and briefly to flashed the audience



Definition of flash (Entry 2 of 4)

1a : a sudden burst of light

b : a movement of a flag in signaling

2 : a sudden and often brilliant burst a flash of wit

3 : a brief time

4a : show, display especially : a vulgar ostentatious display

b archaic : a showy ostentatious person

c : one that attracts notice especially : an outstanding athlete

d : pizzazz

5 obsolete : thieves' slang

6 : something flashed: such as

a : glimpse, look

b : smile

c : a first brief news report

d : flashlight sense 1

e : a quick-spreading flame or momentary intense outburst of radiant heat

f(1) : flashlight sense 2

(2) : a device for producing a flashlight for taking photographs

8 : the rapid conversion of a liquid into vapor



Definition of flash (Entry 3 of 4)

1a : flashy, showy

b : of, relating to, or characteristic of flashy people or things flash behavior

c : of, relating to, or characteristic of persons considered social outcasts flash language

2 : of sudden origin and short duration a flash fire

3 : having or using a solid-state data storage technology that retains data even without a connection to a power source flash memory



Definition of flash (Entry 4 of 4)

: by very brief exposure to an intense altering agent (such as heat or cold) flash fry flash freeze

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Choose the Right Synonym for flash


flash, gleam, glint, sparkle, glitter, glisten, glimmer, shimmer mean to send forth light. flash implies a sudden outburst of bright light. lightning flashed gleam suggests a steady light seen through an obscuring medium or against a dark background. lights gleamed in the valley glint implies a cold glancing light. glinting steel sparkle suggests innumerable moving points of bright light. the sparkling waters glitter connotes a brilliant sparkling or gleaming. glittering diamonds glisten applies to the soft sparkle from a wet or oily surface. glistening wet sidewalk glimmer suggests a faint or wavering gleam. a distant glimmering light shimmer means shining with a wavering light. a shimmering satin dress

Did You Know?

The origin of the word flash is uncertain, although it rhymes with a number of other verbs that also mean forceful, often violent movement that may come to a quick end: dash, lash, crash, slash, clash, gash, bash, splash, smash. These words turn up in English over a fairly long period of time, from dash— the only word in the group with a likely foreign source—in the 14th century, to smash in the 18th century. The element -ash has thus provided a kind of model for new words. The initial fl – that is added to -ash to make flash is also heard in words meaning quick movement, as flee, fly, flicker, and flutter.

Examples of flash in a Sentence


Thunder rumbled and lightning flashed. Cameras flashed as the celebrities passed. A car was sitting on the side of the road with its lights flashing. A message flashed on the screen. The screen flashed a message in black letters. Her eyes flashed with anger.


A brilliant flash lit up the sky. The idea for the movie came to her in a flash of inspiration. They relied on gimmicks and flash to get people's attention. a show with a lot of flash but little substance


flash floods in the local area
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Recent Examples on the Web: Verb

Next up, stand-up comedian Lewis Black (in Lewis Black fashion) playfully flipped the bird to the flashing bulbs. Lauren Sanchez, Vogue, "The Legendary Robin Williams was Missed and Reminisced at the New York City Premiere for Robin Williams: Come Inside My Mind," 14 July 2018 Dave Rosa is being escorted Monday afternoon by a procession of fire trucks and police cars and motorcycles with emergency lights flashing. Fox News, "The Latest: California firefighters salute slain colleague," 25 June 2018 In order to find an explanation for humans’ tendency to underestimate lightning’s splintering branches, researchers asked 10 individuals to look at a series of 180 images flashed across a computer screen. Meilan Solly, Smithsonian, "Why Artists Have so Much Trouble Painting Lightning," 15 June 2018 Video of the performance shows lights flashing as the drop kicks in, with fans going crazy to the beat. Billboard, "Zedd Debuts Epic Remix of BTS' 'Fake Love' At Ultra Music Festival Korea: Watch," 8 June 2018 Police vehicles followed the M1068 with lights flashing during the trip and no crashes or injuries were reported. Kyle Mizokami, Popular Mechanics, "Soldier Steals Armored Vehicle, Takes Joyride Through City," 6 June 2018 The traffic camera video on Tropicana Avenue shows police cars blocking southbound traffic around 10:17 the night of Oct. 1, and ambulances begin appearing with lights flashing at a little after 10:30. David Montero, latimes.com, "Police release fourth batch of materials related to Vegas mass shooting," 31 May 2018 The shiny gray of the elephants’ wet skin was the perfect foil for cobalt waters against a backdrop of yellows, pinks, and purples that flashed across the darkening sky. Meredith Bethune, Condé Nast Traveler, "Why You Should Go on a Boat Safari in Botswana," 23 Apr. 2018 As the names of the 17 victims were read and flashed across the scoreboard, students rang a bell each time and paused for 15 seconds of silence. Thomas Jewell, cleveland.com, "Over 1,000 students walk out at Solon High to protest gun violence," 21 Mar. 2018

Recent Examples on the Web: Noun

There are flashes of humor as well, many coming courtesy of Peña’s motormouthy character. Soren Andersen, The Seattle Times, "‘Ant-Man and the Wasp’: Paul Rudd is back in busy little sequel," 2 July 2018 There were flashes of summer last month, however, when two days in late May reached 95 degrees, Mott said. Elyssa Cherney, chicagotribune.com, "Father's Day weekend will be dangerously hot, meteorologists warn," 14 June 2018 But every so often there were flashes of hesitation. Anna Silman, The Cut, "7 Women on Getting Pete-and-Ariana-ed by Their Exes," 12 June 2018 There are flashes of brilliance, like those five innings Friday night. Gentry Estes, The Courier-Journal, "Bats pitcher Robert Stephenson aims at a return to Cincinnati Reds," 16 May 2018 These could be flashes of light, geometric shapes, distortions of faces, auditory or visual hallucinations, a feeling of familiarity or unreality, the urge to move a specific limb, and so on. Christof Koch, Scientific American, "What Is Consciousness?," 8 May 2018 That's gonna be a flash of light to the face in what is already a natural wonder, so prepare your body and soul for a transformation. Kat Bein, Billboard, "DJ Snake, Virtual Self & More to Headline HARD Red Rocks 2018," 9 Apr. 2018 While there are flashes of brilliance to be found in the language (Williams at his worst can still put words together with an undying lyricism), director Austin Pendleton fails to bring any sense of coherence or vision to this work. Theodore P. Mahne, NOLA.com, "Southern Rep's bill of lesser Tennessee Williams holds limited appeal," 27 Mar. 2018 In ancient Chinese tradition, dreams are a means of exploring the spirit world, or are flashes of a previous life. Linda Rodriguez Mcrobbie, BostonGlobe.com, "How our dreams made us human," 23 Mar. 2018

Recent Examples on the Web: Adjective

If the winds stay to the east, there could be flash snowfalls in the mountains. Miguel Almaguer, NBC News, "Record-breaking cold? PyeongChang braces for frigid weather ahead of Olympics," 5 Feb. 2018 Downpours were dumping a quick inch or two of rain on parts of the Baltimore region, including Ellicott City, on Tuesday, prompting the National Weather Service to issue flash flood warnings. Scott Dance, baltimoresun.com, "Howard County, Baltimore under flash flood warnings," 15 Aug. 2017 Flash flood criteria will be easily met in any location where additional rain falls. Greg Porter, Washington Post, "PM Update: Torrential rain continues on and off through the night, showers taper off on Saturday," 28 July 2017 Flash organizations may even promote upward mobility — if, say, the person brought in to crank out one-line poems can ascend to a supervisory position. Noam Scheiber, New York Times, "The Pop-Up Employer: Build a Team, Do the Job, Say Goodbye," 12 July 2017 Flash memory is used in solid-state drives that have replaced many hard drives, and in smartphones and tablets. David Staats And Kristin Rodine, idahostatesman, "New CEO ‘uniquely qualified’ to lead Micron, co-founded and led successful competitor," 27 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'flash.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of flash


13th century, in the meaning defined at intransitive sense 1


1549, in the meaning defined at sense 1a


circa 1700, in the meaning defined at sense 1a


1970, in the meaning defined above

History and Etymology for flash


Middle English flaschen, of imitative origin

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Learn More about flash

Dictionary Entries near flash






flash back


Phrases Related to flash

in a flash

news flash

quick as a flash

Statistics for flash

Last Updated

14 Sep 2018

Look-up Popularity

Time Traveler for flash

The first known use of flash was in the 13th century

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More Definitions for flash



English Language Learners Definition of flash

 (Entry 1 of 3)

: to shine or give off bright light suddenly or in repeated bursts

: to appear quickly or suddenly

: to move or pass very quickly



English Language Learners Definition of flash (Entry 2 of 3)

: a sudden bright light

: a sudden appearance or occurrence of something

: a fancy or exciting quality or appearance that is meant to attract attention to something that is usually not very good or interesting



English Language Learners Definition of flash (Entry 3 of 3)

: beginning suddenly and lasting only a short time

: very talented


\ ˈflash \
flashed; flashing

Kids Definition of flash

 (Entry 1 of 3)

1 : to shine or give off bright light suddenly Lightning flashed in the sky.

2 : to appear quickly or suddenly A message flashed on the screen.

3 : to come or pass very suddenly A car flashed by.

4 : to show briefly The officer flashed his badge.



Kids Definition of flash (Entry 2 of 3)

1 : a sudden burst of or as if of light a flash of lightning a flash of brilliance

2 : a very short time I'll be back in a flash.



Kids Definition of flash (Entry 3 of 3)

: beginning suddenly and lasting only a short time flash floods


\ ˈflash \

Medical Definition of flash 

: rush sense 2 — compare hot flash

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Comments on flash

What made you want to look up flash? Please tell us where you read or heard it (including the quote, if possible).


occurring twice a year or every two years

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