Definition of flux in English:

Share this entry


Pronunciation: /fləks/


1The action or process of flowing or flowing out: the flux of men and women moving back and forth a localized flux of calcium into the cell
More example sentences
  • In that case, the Lipobead membrane restricted flux of both calcium and the indicator dye Fluo - 3.
  • When the SERCA pump is more active, the net flux of calcium into the cytosol decreases.
  • The calculated water flux shows qualitative agreement with experimental findings for water flux through stratum comeum.
1.1 Medicine An abnormal discharge of blood or other matter from or within the body.
Example sentences
  • It continued till my coming here to Berwick, and then became so vehement, turning to a flux of blood with so great pain as was possible, that I was constrained to keep my bed 15 days.
  • Vasoconstriction of the vessel and fall of pressure slow the blood flux, and immediately, a seal is started.
  • A list of patients admitted during the hospital's first years shows that reasons for admission included hysterick disorders, bloody flux, tertian ague, and melancholy.
1.2 (usually the flux) archaic Diarrhea or dysentery.
Example sentences
  • Both of them are ill with the flux.
2Continuous change: the whole political system is in a state of flux
More example sentences
  • The list is in a state of flux and will continue to be.
  • The governments are in flux and continuity cannot be guaranteed.
  • It's the study and analysis of that flux that seem to have become his life's work.
3 Physics The rate of flow of a fluid, radiant energy, or particles across a given area.
Example sentences
  • A photodiode is mounted on the integrating sphere to measure the radiant flux from the diode laser entering the sphere.
  • Now we use Wien's law to calculate the wavelength of the maximum energy flux for these temperatures.
  • The energy flux was measured with a short-wave ultraviolet intensity meter (UVP, USA).
3.1The amount of radiation or number of particles incident on an area in a given time.
Example sentences
  • Such a measurement, the fluence rate, is defined as the radiation flux from all directions incident on a small sphere in space.
  • If not then to figure out how dangerous is this to you, you need to know how much of the radiation flux reaches your storage unit and how much time you spend in your storage unit.
  • All fluorescent lamps used as sources for UV-B radiation necessarily emit UV-C, UV-A and a small flux of blue visible radiation.
3.2The total electric or magnetic field passing through a surface.
Example sentences
  • Thus, by Faraday's law, which states that a changing magnetic flux induces an electrical field, hence a current is established in the wires which wrap the pickup magnet.
  • The magnetic flux is measured by external coils, from which the conductivity inside the object can be calculated.
  • Alternatively, actively powered Hall effect sensors can measure the absolute magnetic flux.
4A substance mixed with a solid to lower its melting point, used especially in soldering and brazing metals or to promote vitrification in glass or ceramics.
Example sentences
  • The water acts as a simple flux to lower the melting point of some minerals.
  • In the case of oxidation-resistant metals the reaction is facilitated by the use of a chemical flux or metal powder.
  • Later imitators did produce high temperature ceramics using such fluxes, such as bone porcelain, like Beleek.
4.1A substance added to a furnace during metal smelting or glassmaking that combines with impurities to form slag.
Example sentences
  • Lead has been removed from copper alloy melts by the application of silicate fluxes or slags.
  • Rotary furnaces generally use Na 2 CO 3 and iron as fluxes, which produce a fluid, low-melting slag.
  • During iron making, iron ore, coke heated air and limestone or other fluxes are fed into a blast furnace.


[with object]
Treat (a metal object) with a flux to promote melting.
Example sentences
  • It was considered such ideal fluxing ore that the El Paso smelter paid the costs for shipping it by rail and processed the ore at no charge to assure a steady supply.
  • The zinc alloys melt in less time and do not require fluxing or degassing as is common with aluminum alloys.
  • After fluxing, all dirt and impurities will float on top of the melt, and may be skimmed off with the ladle.


Late Middle English: from Latin fluxus, from fluere 'to flow'.

  • affluent from Late Middle English:

    From Latin affluere ‘flow towards’, affluent was originally used to describe water either flowing towards a place or flowing freely without any restriction. It later came to mean ‘abundant’ and then ‘wealthy’, a meaning which dates from the mid 18th century. Related words, all based on Latin fluere ‘to flow’ are fluent (late 16th century) and fluid (Late Middle English); flume (Middle English) originally a stream; flux (Late Middle English) a state of flowing; effluent (Late Middle English) something that flows out; and superfluous (Late Middle English) ‘overflowing’.

Words that rhyme with flux

crux, dux, lux, luxe, tux

For editors and proofreaders

Syllabification: flux

Share this entry

What do you find interesting about this word or phrase?

Comments that don't adhere to our Community Guidelines may be moderated or removed.