\ ˈblü How to pronounce blue (audio) \
bluer; bluest

Definition of blue

 (Entry 1 of 3)
1 : of the color whose hue is that of the clear sky : of the color blue (see blue entry 2 sense 1) a blue jacket her bright blue eyes The house is blue with white shutters.
2a : bluish the blue haze of tobacco smoke
b : discolored by or as if by bruising blue with cold
c : bluish gray a blue cat
3a : low in spirits : melancholy has been feeling blue
b : marked by low spirits : depressing a blue funk things looked blue
4 : wearing blue the blue team
5 of a woman : learned, intellectual … the ladies were very blue and well-informed …— W. M. Thackeray
6 : puritanical … a blue Sunday city …— James Street
7a : profane, indecent a blue movie
b : off-color, risqué blue jokes
8 music : of, relating to, or used in blues (see blues sense 3) a blue song
9 US politics : tending to support Democratic candidates or policies As has become increasingly clear over the past few general elections, with their red states and blue states, an American Presidential campaign is no longer truly national.— Hendrik Hertzberg — compare purple sense 3, red sense 5
blue in the face
: extremely exasperated argued until he was blue in the face


Definition of blue (Entry 2 of 3)
1 : a color whose hue is that of the clear sky or that of the portion of the color spectrum lying between green and violet Blue is his favorite color. shades of blue
2a : a pigment or dye that colors blue
b : bluing adding blue to the laundry
3a : blue clothing or cloth will be wearing blue
b blues plural : a blue costume or uniform wearing their dress blues
4a : a Union soldier in the American Civil War
b often capitalized : the Union army the Blue versus the Gray
5a(1) : sky
(2) : the far distance disappeared into the blue
b : sea
6 : a blue object
7 : bluestocking praised the writings of her fellow blues
8 biology : any of numerous small chiefly blue butterflies (family Lycaenidae)
9 : bluefish fishing for blues
11 physics : one of the three colors (see color entry 1 sense 15) that quarks have in the theory of quantum chromodynamics One cannot have a single quark on its own because it would have a color (red, green, or blue). Instead, a red quark has to be joined to a green and a blue quark by a "string" of gluons (red + green + blue = white). Such a triplet constitutes a proton or a neutron.— Stephen Hawking
out of the blue
: without advance notice : unexpectedly the job offer came out of the blue


blued; blueing or bluing; blues
Definition of blue (Entry 3 of 3)

transitive verb

: to make (something) blue in color: such as
a : to dye, tint, or paint (something) blue Last, the generation of the grandmothers, in immaculately blued hair…— John Updike Tattoos blued his upper arms.— Jerry Spinelli
b : to heat (iron or steel) to about 550 to 600 degrees Fahrenheit so that it acquires a protective bluish coating the blued barrel of the gun Between banks shrouded with snow, the river gleamed darkly, like blued steel with gold chips of sunlight dancing on each riffle.— Pete Bodo

intransitive verb

: to turn blue their blueing fingers
blue the air
: to curse angrily He sliced the air with his fists and blued the air with his mouth.— Steve Kelley I have been stealing my father's copy (of Massachusetts Wildlife) for a long time, but last week he found an issue on my desk and blued the air a bit.— Stephen King Donovan

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Other Words from blue


bluely adverb
blueness noun

Examples of blue in a Sentence

Adjective shocked at the blue banter she heard on that satellite-radio talk show a cold, dreary day always leaves me blue Noun Her favorite color is blue. a mixture of blues and greens They sailed off into the blue.
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Recent Examples on the Web: Adjective Optometrists refer to overexposure to blue light as Computer Vision Syndrome. Laken Brooks, Forbes, "People Report More Headaches And Migraines During Covid-19," 3 Mar. 2021 Don't bring your cellphone and its harmful blue light to bed. Sandee Lamotte, CNN, "Smartphone addiction ruins sleep, study says, but you can fight back," 2 Mar. 2021 Produced by the Federal Seaboard Terra Cotta Corporation from plaster molds, the main body of each handmade letter was composed of white terra-cotta blocks that protruded six inches from a starkly contrasting blue-green background. New York Times, "Atop the McGraw-Hill Building, the Name Stays," 26 Feb. 2021 Around Easter, the Fourth of July, Halloween, and Thanksgiving, lifers filled the hall with enormous craft pumpkins and rabbits, and also red-white-and-blue bunting, for use on the South Lawn. Susannah Jacob, The New Yorker, "The Secret Life of the White House," 24 Feb. 2021 The kitchen has a hushed quality due to blue-green Japanese tiles, which give the back wall a dark iridescence. J. S. Marcus, WSJ, "An Australian Couple Demolished Their Home to Build a Retirement Retreat," 24 Feb. 2021 The planters come in black, brown, blue-green, and yellow, with sizes ranging from about 7 inches to 16 inches in diameter. Jessica Bennett, Better Homes & Gardens, "Fluted Detailing Is the Trendy Texture That Adds Classic Style to Furnishings," 23 Feb. 2021 The video shows a descent through 3,000 feet of blue-green ice, which suddenly terminates, opening up into dark seawater. Matt Simon, Wired, "Scientists Accidentally Discover Strange Creatures Under a Half Mile of Ice," 15 Feb. 2021 This specific blue-green shade signifies awareness and support for the more than 21,410 American women› who will receive a diagnosis of ovarian cancer this year. Korin Miller, Good Housekeeping, "What You Should Know About Your BRCA Status And Ovarian Cancer Risk," 9 Feb. 2021 Recent Examples on the Web: Noun A year later, out of the blue, Fisher contacted him and asked him to work on a new Cruise parody video in which Fisher would have Cruise conceding his presidential bid, his face morphing into a Cruise deepfake in the sketch’s final moments. Jeremy Kahn, Fortune, "Deepfake master behind those viral Tom Cruise videos says the technology should be regulated," 5 Mar. 2021 Don’t verify your Social Security number or any other personal information to anyone who calls out of the blue. Susan Tompor, Detroit Free Press, "Social Security scammers now text pictures of phony badges," 4 Mar. 2021 Then out of the blue over the holidays, Spence heard from like-minded Beck Center alum Kathleen Rooney Faubel, who lives in New York City. John Benson, cleveland, "Beck Center for the Arts streaming fundraiser ‘Beck Broadway Alums In Concert’," 3 Mar. 2021 For many, Amanda's success seemed to have come out of the blue. Dr. Richard Osibanjo, Forbes, "The Next Generation Leader: Lessons From Amanda Gorman," 24 Feb. 2021 Most of the blue is gone from the receiver, and the rest is thinning. The Editors, Field & Stream, "29 Classic Guns: Old Rifles, Collectible Shotguns, and Other Rare Guns," 23 Feb. 2021 The vote was 55-45, and came somewhat out of the blue after a GOP congresswoman recounted a conversation during the Jan. 6 riot in which Trump rebuffed the House Republican leader’s pleas to intervene. Todd J. Gillman, Dallas News, "Watch live: Senate votes to consider calling witnesses at Trump impeachment trial," 13 Feb. 2021 On the way, something appears, out of the blue, in the sky. Jason Kehe, Wired, "Bliss Is the Worst Kind of Open-Ended Sci-Fi Movie," 5 Feb. 2021 The charity -- which provides food on the weekends for elementary school children who might otherwise go hungry -- has been working with Jackson for about three years, but this surge in donations came completely out of the blue. Steve Gardner, USA TODAY, "Buffalo Bills fans overwhelm charity with donations after Lamar Jackson's injury," 17 Jan. 2021 Recent Examples on the Web: Verb The home uniforms, which FAU wore versus the 49ers, have blue as the dominant color once again. Khobi Price,, "FAU debuts new jerseys to kick off 20th season, Willie Taggart era," 3 Oct. 2020 To ensure that John Cornyn, Chip Roy and the rest of the Texas Republicans stop putting us in danger, voter blue up and down the ballot in November. Taylor Goldenstein,, "Travis County GOP under investigation for COVID-19 order violations," 26 Aug. 2020 There are signs that Texas, due to changing demographics, may be the next Electoral College giant to turn from red, if not to blue, then at least to purple. John A. Farrell, The New Republic, "TNR Newsletters. Must reads. 5 days a week.," 16 Apr. 2020 So why won't blue shampoo cut it for keeping cool brunettes cool? Taylore Glynn, Marie Claire, "Brunettes: Green Shampoo Is Here to Save Your Color," 23 Jan. 2020 Ruscillo has studied the production of the ancient purple dye, including experimenting with it to make colors from pink to blue to almost black, though she isn't involved in the excavations on Chrysi. Fox News, "Gold and jewels found on Minoan Island devoted to the color purple," 12 Dec. 2019 The pair were all smiles for the appearance at St. James’s Palace, where Kate blue a royal blue Issa dress that matched her sapphire engagement ring, which once belonged to William’s mother Princess Diana. Stephanie Petit,, "See the Sweet Photos of Meghan and Harry (and Kate and William!) the Queen Has on Display at Home," 25 July 2019 Give classic orange and blue a dose of edge with abstract prints and a hit of dark à la Samantha Angelo. Laurel Benedum, ELLE Decor, "7 Decadent Rooms Inspired By This Weekend's Chicest Celebrity Outfits," 4 June 2019 Stop painting the same models blue and calling it revolutionary. Sandra Salibian | Wwd,, "Designer Jeremy Scott responds to social media controversy about Moschino campaign post," 26 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'blue.' 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 blue


13th century, in the meaning defined at sense 1


14th century, in the meaning defined at sense 1


1606, in the meaning defined at transitive sense

History and Etymology for blue

Adjective, Noun, and Verb

Middle English, from Anglo-French blef, blew, of Germanic origin; akin to Old High German blāo blue; akin to Latin flavus yellow

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Learn More about blue

Time Traveler for blue Time Traveler

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

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Statistics for blue

Last Updated

8 Mar 2021

Cite this Entry

“Blue.” Dictionary, Merriam-Webster, Accessed 9 Mar. 2021.

Style: MLA
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More Definitions for blue



English Language Learners Definition of blue

 (Entry 1 of 2)

: having the color of the clear sky
: sad or unhappy



English Language Learners Definition of blue (Entry 2 of 2)

: the color of the clear sky
literary : the sky or the sea


\ ˈblü How to pronounce blue (audio) \

Kids Definition of blue

 (Entry 1 of 2)
1 : the color of the clear daytime sky
2 : blue clothing or cloth
out of the blue
: suddenly and unexpectedly

Other Words from blue

bluish adjective


bluer; bluest
Kids Definition of blue (Entry 2 of 2)
1 : of the color of the sky : of the color blue blue ink
2 : sad sense 1 Why are you so blue?


\ ˈblü How to pronounce blue (audio) \
bluer; bluest

Medical Definition of blue

 (Entry 1 of 2)
: of the color blue


Medical Definition of blue (Entry 2 of 2)
1 : a color whose hue is that of the clear sky or that of the portion of the color spectrum lying between green and violet
2 : a pigment or dye that colors blue — see prussian blue

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More from Merriam-Webster on blue

Thesaurus: All synonyms and antonyms for blue

Nglish: Translation of blue for Spanish Speakers

Britannica English: Translation of blue for Arabic Speakers

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