\ ˈfləks How to pronounce flux (audio) \

Definition of flux

 (Entry 1 of 2)

1 : a flowing of fluid from the body: such as
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

Synonyms: Verb

Antonyms: Verb

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Examples of flux in a Sentence

Noun the English language is always in a state of flux January typically brings a great flux of returns to department stores. Verb a solid will flux more quickly under pressure
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Recent Examples on the Web: Noun Most around the league expect a lot more movement in the coming days, which will, predictably, continue to throw this mock draft into flux. Jeremy Woo, SI.com, "2019 NBA Mock Draft 10.0: Anthony Davis Trade Shakes Up the Lottery," 17 June 2019 And the neurological areas responsible for life skills like judgment and decision-making are still in flux. Christina Capatides, CBS News, "American kids with money and privilege are more likely to binge drink," 15 Sep. 2019 And maybe the role of the persona, a crucial concept in pop history, is in flux. Spencer Kornhaber, The Atlantic, "The Plot Against Persona," 15 Sep. 2019 Bama’s front line has been in flux early this season because of injuries to Chris Owens and Emil Ekiyor. Mike Rodak | Mrodak@al.com, al, "A look at the key factors in Alabama-South Carolina," 14 Sep. 2019 The planning remains in flux, and White House officials have been known to cancel visits at the last minute. Tracy Jan, Washington Post, "HUD Secretary Ben Carson and top Trump officials to visit California as White House ramps up homeless push," 13 Sep. 2019 They are much fancied against a Fiorentina side that is also in-flux after a summer of change. SI.com, "This Weekend's 7 Must-Watch Games as Club Football Finally Returns," 12 Sep. 2019 That charge is a big reason why UTSA and Army are contracted to play three more times, with games in 2020, 2022 and 2023, but those games have not been announced and are in flux because the Roadrunners are overbooked in two of those years. Nick Talbot, ExpressNews.com, "UTSA-Army a fitting game for Military City USA," 11 Sep. 2019 But the larger goal — a regional realignment — remains very much in flux. New York Times, "The Secret History of the Push to Strike Iran," 4 Sep. 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

20 Oct 2019

Time Traveler for flux

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

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More Definitions for flux


How to pronounce flux (audio)

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

Thesaurus: All synonyms and antonyms for flux

Rhyming Dictionary: Words that rhyme with 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).


meddlesome, informal, or unofficial

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