\ˈfləks \

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

affluence, income, inflow, influx, inpouring, inrush

Synonyms: Verb

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

Antonyms: Noun

outflow, outpouring

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

For the hardcore Cavaliers fan, it's been a season-long theme that the team's roster has been in constant flux from Game 1 last fall to today. cleveland.com, "Cedi Osman: 10 things to know about the Cavaliers forward," 15 May 2018 The island, called Bhasan Char, is more of a massive sandbar cut by canals and in constant flux amid shifting ocean currents. Jason Patinkin, Washington Post, "Rohingya refugees escaped massacres in Burma. Now they face another deadly force: Monsoons.," 4 May 2018 In hiring a new president, Chicago State is seeking permanency for a role that has been in constant flux. Dawn Rhodes, chicagotribune.com, "Chicago State chooses three finalists for president," 2 May 2018 Further, Myers’ absence – first due to a nerve irritation in his throwing arm and now a strained left oblique – is the biggest reason the Padres’ outfield has been in constant flux. Kevin Acee, sandiegouniontribune.com, "Padres notes: Myers-Hosmer combo waylaid again; Jankowski hits; Maki hit," 29 Apr. 2018 Instead ecosystems are temporary, chaotic assemblages of species, with relations between them and their environment in constant flux. Charles C. Mann, WSJ, "‘Silent Spring & Other Writings’ Review: The Right and Wrong of Rachel Carson," 26 Apr. 2018 On set, the legions of specialists and consultants working on the minutiae took orders from Kubrick, whose conception of the whole remained in constant flux. Junot Díaz, The New Yorker, "“2001: A Space Odyssey”: What It Means, and How It Was Made," 17 Apr. 2018 Players come together for a few days then scatter, and the combinations and permutations are in constant flux. Brian Straus, SI.com, "USMNT's New Talents Establish Own Culture, Tactical Identity as Uncertain Future Looms," 28 Mar. 2018 Center Tyler Zeller also missed Monday's game, though his status has been in constant flux. Matt Velazquez, Milwaukee Journal Sentinel, "Cavs 124, Bucks 117: Defensive miscues are too much to overcome," 19 Mar. 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


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


see flux entry 1

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Statistics for flux

Last Updated

20 Oct 2018

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

: a substance used for helping to melt or join metals


\ˈfləks \

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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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).


playful or foolish behavior

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