fluid

adjective
flu·​id | \ ˈflü-əd How to pronounce fluid (audio) \

Definition of fluid

 (Entry 1 of 2)

1a : having particles that easily move and change their relative position without a separation of the mass and that easily yield to pressure : capable of flowing a long screw that forces the fluid chocolate through fine openingsTechnical Survey
b : subject to change or movement boundaries became fluid
2 : characterized by or employing a smooth easy style the ballerina's fluid movements fluid recitation of his lines
3a : available for various uses a fluid computer program
b : liquid sense 4 fluid assets

fluid

noun

Definition of fluid (Entry 2 of 2)

: a substance (such as a liquid or gas) tending to flow or conform to the outline of its container

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Other Words from fluid

Adjective

fluidly adverb
fluidness noun

Noun

fluidal \ ˈflü-​ə-​dᵊl How to pronounce fluidal (audio) \ adjective
fluidally \ ˈflü-​ə-​dᵊl-​ē How to pronounce fluidally (audio) \ adverb
fluidlike \ ˈflü-​ə-​dᵊl-​ˌlīk How to pronounce fluidlike (audio) \ adjective

Synonyms & Antonyms for fluid

Synonyms: Adjective

Antonyms: Adjective

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Examples of fluid in a Sentence

Adjective a substance in a fluid state warm the jam until it is fluid, then spread it over the cake Noun Please check the fluids in the car's engine. She needs to drink plenty of fluids. Fluid leaked from the car's engine. a bottle of yellow fluid
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Recent Examples on the Web: Adjective On the defensive end, Portland forced Philadelphia to play a disjointed style instead of their typically fluid attack. Julia Poe, orlandosentinel.com, "Portland Timbers book first spot in MLS final with 2-1 win over Philadelphia," 5 Aug. 2020 The situation is sufficiently fluid that Churchill Downs CEO Bill Carstanjen called Gov. Andy Beshear Tuesday to confer about contingencies. Tim Sullivan, The Courier-Journal, "Fans at the Kentucky Derby seem more unlikely after Indy 500 shifts gears," 5 Aug. 2020 Details remain fluid until the Mountain West issues an official release, which is expected following a midday meeting of its board of directors. Kirk Kenney, San Diego Union-Tribune, "Aztecs expecting Mountain West to announce 10-game football schedule," 5 Aug. 2020 Then again, considering how fluid everything is with the pandemic, who knows if these will actually be, in order, the Hoosiers’ final three games. Jon Blau, The Indianapolis Star, "Breaking down IU football's very different 2020 Big Ten schedule," 5 Aug. 2020 Shockwaves rapidly mix fluid streams, which is a requirement for a supersonic-air ramjet. Caroline Delbert, Popular Mechanics, "If We Mix Jet Fuel Using Shockwaves, We Can Get to Mars Faster," 4 Aug. 2020 At one Westlake store, a mother was overheard recently reassuring her brood that school will be back, even if the details are a bit fluid right now. Carol Kovach, cleveland, "Grab some face masks with your school supplies this fall: West Shore Chatter," 4 Aug. 2020 Barnhart cleanly backhanded the ball into his mitt and rifled a throw to shortstop Freddy Galvis at second base in one fluid motion. Bobby Nightengale, The Enquirer, "How Tucker Barnhart lifted the Cincinnati Reds with his smarts and his arm," 4 Aug. 2020 The whole festival was permeated with a sense of gentleness, openness and beauty, as organic and wholesome as a hippie commune, yet with the high artistry, exquisite design and singularly fluid choreography Pilobolus is known for. Christopher Arnott, courant.com, "Review: Pilobolus’ Five Senses Festival, reimagined for the pandemic, delivers safety and inspiration," 3 Aug. 2020 Recent Examples on the Web: Noun Looking for better protection against dust, fluid, and, mites? Sara Rodrigues, House Beautiful, "Get the Best Night's Sleep by Deep-Cleaning Your Mattress," 31 July 2020 Named after the 19th-century physicist Osborne Reynolds, the concept is especially useful for predicting when a fluid will transition to turbulent flow. Jennifer Ouellette, Ars Technica, "Human sperm swim more like otters than eels, study finds," 31 July 2020 Buoyancy creates upward force that’s exerted on objects submerged in fluid. Molly Longman, refinery29.com, "Does Being Underwater Stop Your Period?," 9 July 2020 The virus that causes Covid-19 was not found in their brain fluid, meaning the virus does not appear to directly attack the brain. Jessie Yeung, CNN, "Coronavirus pandemic could cause wave of brain damage, scientists warn," 8 July 2020 Either way, if your oil looks a little too glittery for comfort or smells too much like another fluid (such as coolant), that’s a good time to get an oil analysis done to determine how that may have happened. Ezra Dyer, Popular Mechanics, "For Motor Oil, How Old Is Too Old?," 14 June 2020 Pimple patches are also great for whiteheads: they're made out of hydrocolloid, which absorbs and sucks out the fluid in your pimple. Yerin Kim, Seventeen, "How to Get Rid of Pimples Overnight, According to the Acne Experts," 10 June 2020 When this happens, the alveoli can fill with fluid and debris. Anchorage Daily News, "The science of smoking and COVID-19," 12 July 2020 As the disease worsens, the lungs begin to fill with fluid, which might change the nature of the cough. Sandee Lamotte, CNN, "Covid-19 symptoms: What we know now and what to do," 10 July 2020

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

Adjective

1603, in the meaning defined at sense 1a

Noun

1661, in the meaning defined above

History and Etymology for fluid

Adjective and Noun

French or Latin; French fluide, from Latin fluidus, from fluere to flow; akin to Greek phlyzein to boil over

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Time Traveler for fluid

Time Traveler

The first known use of fluid was in 1603

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Statistics for fluid

Last Updated

9 Aug 2020

Cite this Entry

“Fluid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluid. Accessed 11 Aug. 2020.

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More Definitions for fluid

fluid

adjective
How to pronounce fluid (audio)

English Language Learners Definition of fluid

 (Entry 1 of 2)

: capable of flowing freely like water
used to describe something that can change easily or that changes often
: having or showing a smooth and easy style

fluid

noun

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

: a substance that is able to flow freely : a liquid substance

fluid

adjective
flu·​id | \ ˈflü-əd How to pronounce fluid (audio) \

Kids Definition of fluid

 (Entry 1 of 2)

1 : capable of flowing like a liquid or gas fluid lava
2 : having a graceful or flowing style or appearance a dancer's fluid movement

Other Words from fluid

fluidly adverb

fluid

noun

Kids Definition of fluid (Entry 2 of 2)

: something that tends to flow and take the shape of its container

fluid

adjective
flu·​id | \ ˈflü-əd How to pronounce fluid (audio) \

Medical Definition of fluid

 (Entry 1 of 2)

: having particles that easily move and change their relative position without a separation of the mass and that easily yield to pressure : capable of flowing

fluid

noun

Medical Definition of fluid (Entry 2 of 2)

: a substance (as a liquid or gas) tending to flow or conform to the outline of its container specifically : one in the body of an animal or plant — see cerebrospinal fluid, seminal fluid

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More from Merriam-Webster on fluid

Thesaurus: All synonyms and antonyms for fluid

Rhyming Dictionary: Words that rhyme with fluid

Spanish Central: Translation of fluid

Nglish: Translation of fluid for Spanish Speakers

Britannica English: Translation of fluid for Arabic Speakers

Britannica.com: Encyclopedia article about fluid

Comments on fluid

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