\ ˈfləks How to pronounce flux (audio) \

Definition of flux

 (Entry 1 of 2)

1 : a flowing of fluid from the body: such as
a : diarrhea
b : dysentery
2 : a continuous moving on or passing by (as of a stream)
3 : a continued flow : flood a flux of words
4a : influx
b : change, fluctuation in a state of flux the flux following the death of the emperor
5 : a substance used to promote fusion (as of metals or minerals) especially : one (such as rosin) applied to surfaces to be joined by soldering, brazing, or welding to clean and free them from oxide and promote their union
6 : the rate of transfer of fluid, particles, or energy across a given surface


fluxed; fluxing; fluxes

Definition of flux (Entry 2 of 2)

transitive verb

1 : to cause to become fluid
2 : to treat with a flux

intransitive verb

: to become fluid : fuse

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Synonyms & Antonyms for flux

Synonyms: Noun

change, fluctuation, inconstancy, oscillation

Synonyms: Verb

deliquesce, fuse, liquefy (also liquify), melt, run, thaw

Antonyms: Verb

harden, set, solidify

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Examples of flux in a Sentence


the English language is always in a state of flux January typically brings a great flux of returns to department stores.


a solid will flux more quickly under pressure
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Recent Examples on the Web: Noun

At the time, voice technology was still in flux, and many regulatory decisions proved to have lasting consequences. Tina Tallon, The New Yorker, "A Century of “Shrill”: How Bias in Technology Has Hurt Women’s Voices," 3 Sep. 2019 As a tourist destination, Nantucket’s population is always in flux as are the movements of its visitors. NBC News, "Researchers are tracking sharks to keep beachgoers safer," 28 Aug. 2019 This illustrates a paradoxical feature of the political divide: a combination of intellectual flux and partisan rigidity. The Economist, "Elizabeth Warren, saviour of capitalism," 21 June 2019 The Pac-12 remains in flux and Colorado is likely the conference’s most stable squad. Michael Shapiro, SI.com, "Five Offseason Sleeper Teams That Could Make Noise in 2019–20," 14 June 2019 Sharing the gloves with incumbent stopper Alphonse Areola, the Parisians were eliminated at the last 16 stage by Manchester United, and Buffon's future was once again in flux. SI.com, "6 Players Who Came Back Home to Finish Their Careers," 22 Aug. 2019 Life in flux has defined Kelsey Lu’s 20s — ever since the artist got her break touring with Southern rap crew Nappy Roots around 2011. Los Angeles Times, "How Kelsey Lu found her tribe among L.A.'s black art scene," 21 Aug. 2019 The defensive line has been in flux because some key players are working their way back from injuries. Michelle Gardner, azcentral, "ASU practice report: Sun Devils looking to solidify both lines," 16 Aug. 2019 But though bobbleheads themselves haven’t really changed, the collection at the Bobblehead Hall of Fame and Museum is constantly in flux. Jennifer Billock, Smithsonian, "Visit the World’s Only Bobblehead Hall of Fame and Museum," 15 Aug. 2019

Recent Examples on the Web: Verb

Next, clean and flux a shutoff valve for the cold side and slide it over the tubing end place and solder it in place. Steve Willson, Popular Mechanics, "How To Install An Electric Water Heater," 24 Aug. 2018

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


14th century, in the meaning defined at sense 1


15th century, in the meaning defined at transitive sense 1

History and Etymology for flux

Noun and Verb

Middle English, from Anglo-French & Medieval Latin; Anglo-French, from Medieval Latin fluxus, from Latin, flow, from fluere to flow — more at fluid

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Statistics for flux

Last Updated

8 Sep 2019

Look-up Popularity

Time Traveler for flux

The first known use of flux was in the 14th century

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More Definitions for flux



English Language Learners Definition of flux

: a series of changes : continuous change
technical : a substance used for helping to melt or join metals


\ ˈfləks How to pronounce flux (audio) \

Medical Definition of flux

1a : a flowing or discharge of fluid from the body especially when excessive or abnormal: as
(1) : diarrhea
(2) : dysentery
b : the matter discharged in a flux
2 : the rate of transfer of fluid, particles, or energy across a given surface

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More from Merriam-Webster on flux

Rhyming Dictionary: Words that rhyme with flux

Thesaurus: All synonyms and antonyms for flux

Spanish Central: Translation of flux

Nglish: Translation of flux for Spanish Speakers

Britannica English: Translation of flux for Arabic Speakers

Britannica.com: Encyclopedia article about flux

Comments on flux

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


concealment of treason or felony

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