flux

American  

[fluhks] / flʌks /

noun

fluxes plural

1. a flowing or flow.

   Synonyms:

   livestream, flood, current, course

2. the flowing in of the tide.

3. continuous change, passage, or movement.

   His political views are in a state of flux.

4. Physics.

   1. the rate of flow of fluid, particles, or energy.

   2. a quantity expressing the strength of a field of force in a given area.

5. Chemistry, Metallurgy.

   1. a substance used to refine metals by combining with impurities to form a molten mixture that can be readily removed.

   2. a substance used to remove oxides from and prevent further oxidation of fused metal, as in soldering or hot-dip coating.

   3. (in the refining of scrap or other metal) a salt or mixture of salts that combines with nonmetallic impurities, causing them to float or coagulate.

6. fusion.

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verb (used with object)

1. to melt; make fluid.

2. to fuse by the use of flux.

3. Obsolete. to purge.

verb (used without object)

1. to flow.

flux British  

/ flʌks /

noun

1. a flow or discharge

2. continuous change; instability

3. a substance, such as borax or salt, that gives a low melting-point mixture with a metal oxide. It is used for cleaning metal surfaces during soldering, etc, and for protecting the surfaces of liquid metals

4. metallurgy a chemical used to increase the fluidity of refining slags in order to promote the rate of chemical reaction

5. a similar substance used in the making of glass

6. physics

   1. the rate of flow of particles, energy, or a fluid, through a specified area, such as that of neutrons ( neutron flux ) or of light energy ( luminous flux )

   2. the strength of a field in a given area expressed as the product of the area and the component of the field strength at right angles to the area

      magnetic flux

      electric flux

7. pathol an excessive discharge of fluid from the body, such as watery faeces in diarrhoea

8. the act or process of melting; fusion

9. (in the philosophy of Heraclitus) the state of constant change in which all things exist

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verb

1. to make or become fluid

2. (tr) to apply flux to (a metal, soldered joint, etc)

3. (tr) an obsolete word for purge

flux Scientific  

/ flŭks /

1. The rate of flow of fluids, particles, or energy across a given surface or area.

2. The presence of a field of force in a region of space, represented as a set of lines indicating the direction of the force. The density of the lines indicates the strength of the force. Lines used to represent magnetic fields in depictions of magnets, for example, follow the lines of flux of the field.

3. See also field magnetic flux

4. A measure of the strength of such a field.

5. A readily fusible glass or enamel used as a base in ceramic work.

6. An additive that improves the flow of plastics during fabrication.

7. A substance applied to a surface to be joined by welding, soldering, or brazing to facilitate the flowing of solder and prevent formation of oxides.

8. A substance used in a smelting furnace to make metals melt more easily.

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Other Word Forms

Derived Forms

• nonflux
  noun
• superflux
  noun
• transflux
  noun

Inflected Forms

Nouns

• fluxes
  plural

Etymology

Origin of flux

First recorded in 1350–1400; Middle English, from Latin fluxus “a flowing,” equivalent to fluc-, variant stem of fluere “to flow” + -tus, noun and participle suffix

Explanation

The noun flux describes something that constantly changes. If your likes, dislikes, attitudes, dreams, and even friends are changing all the time, you may be in flux. Flux can also mean being unsure about a decision. Suppose you just had a great job interview and suddenly your friend invites you to go to Australia with her. You don't know what to do because you don't want to miss a call about the job — or Sydney! You're in flux until you hear from the potential employer. Another kind of flux is liquid moving or flowing, like the flux of water under a sheet of melting ice.

Example Sentences

See Examples For:

flux fluxes

Ristroph, Sprinkle, and their colleagues described this explanation as the momentum flux theory, which focuses on the way swirling water carries momentum through the sprinkler.

From Science Daily ● Jul. 17, 2026

A lot is in flux for graduate students.

From The Wall Street Journal ● Jul. 1, 2026

The figures in her uncategorizable works are in experimental flux, trying on masks to see what might prove effective in a given situation.

From Los Angeles Times ● Jun. 29, 2026

And that judgement has to account for the fact that the period since Brexit has been a time of huge global flux.

From BBC ● Jun. 23, 2026

After the GAC dashed his dream of a reactor, Ernest mobilized the Rad Lab to find another way of generating a heavy neutron flux.

From "Big Science" by Michael Hiltzik

They also contributed to important measurements involving proton and helium fluxes and helped analyze carbon nuclei data.

From Science Daily ● May 14, 2026

The researchers set out to study both biodiversity -- plants, insects, vertebrates -- and changes in how food webs function -- biomass, trophic structure, energy fluxes.

From Science Daily ● Feb. 21, 2024

The authors have effectively disproven previous claims suggesting that the sulfur anomaly in Planetary Nebulae was a result of underestimated higher sulfur ionization stages or weak sulfur line fluxes.

From Science Daily ● Feb. 7, 2024

Some of this energy is used for photosynthesis in natural forests or to produce electricity in solar "forests" -- but most returns to the atmosphere as fluxes of energy, heating it up.

From Science Daily ● Dec. 13, 2023

He has nothing to say as to whether fluxes are used or not.

From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius