\ 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 But Mario Galindo, a noted Bolivian political science professor, said the political situation was confusing and in flux. Clifford Krauss, New York Times, "Bolivia’s Interim Leader Pledges to ‘Reconstruct Democracy’," 13 Nov. 2019 Michigan State's blocking front, on the other hand, has been affected by injuries and has been in flux in recent weeks. Rainer Sabin, Detroit Free Press, "Michigan football vs. Michigan State football: From QB to special teams, who has the edge?," 13 Nov. 2019 While details remain in flux, Moore said one possible plan would retain the existing tax rates at 10 percent and 12 percent for the bottom two tax rates, as well as the existing top three tax rates. Jeff Stein, Washington Post, "Trump advisers exploring tax proposal that would lower “middle class” rate to 15 percent," 12 Nov. 2019 The company noted the positive impact of trading gains, particularly in the market for fuel oil, which has been in flux ahead of the introduction of new rules limiting the sulfur content of shipping fuel. Kelly Gilblom, chicagotribune.com, "Shell beats profit estimates, warns of slower share buyback," 12 Nov. 2019 Competing against the Soviet Union when air power was in flux, and deciding which new airplane would be the right one was uncertain, these companies built the F-100 through F-106 in just a few short years. Wired, "Opinion: Let's Ensure Tech Innovation Gets to the Military," 1 Nov. 2019 All of that section is in flux because the entrance to the park, including its famed fountains, is being restructured. Dewayne Bevil, orlandosentinel.com, "Mickey on the move (again) at Epcot. Here’s where he’ll meet guests in 2020," 31 Oct. 2019 The trade would’ve immediately solidified the Browns left tackle position, which has been in flux since future Hall of Famer Joe Thomas retired before last season. Mary Kay Cabot, cleveland, "Browns didn’t trade for Trent Williams or make other deals on Tuesday before the 4 p.m. deadline," 29 Oct. 2019 Brown was drafted into a Bengals organization in flux. Oliver Staley, Quartz at Work, "How the NFL separates good from great when evaluating talent," 24 Oct. 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

17 Nov 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

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