Definition of flux in English:



  • 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’
    • ‘A high sensitivity coefficient for a particular enzyme indicates that this enzyme exerts a strong control over flux through the pathway.’
    • ‘Consequently, reducing enzyme activity by much as 50% has a negligible effect on flux through the pathway.’
    • ‘Although not proven, it is logical to assume that capillary basement membrane thickening impairs the flux of nutrients and possibly the migration of white blood cells.’
    • ‘Roots from detopped tomato plants were inserted in a chamber under constant pressure and sap flux was measured continuously.’
    • ‘The flux of ammonium through the photorespiratory nitrogen cycle has been estimated to be 10 times higher than that resulting from primary assimilation.’
    • ‘When the SERCA pump is more active, the net flux of calcium into the cytosol decreases.’
    • ‘This might be the case with flux through aluminium foil into which holes have been punched, for example.’
    • ‘Second, the population flux will converge towards those countries that provide the more generous social benefits or the best living conditions.’
    • ‘The increasing flux of people out of the country determined the GDR government to close the border into the FRG.’
    • ‘Human perception is merely included within the flux of images that is reality.’
    • ‘They do so by adjusting the flux of hormones in the host's body, so that it just keeps growing into an oversized infant.’
    • ‘Impressionism arose from the tension between a focused, stabilizing attention on the one hand, and the continuous flux of sensation on the other.’
    • ‘The measurement of residence times requires a knowledge of the flux of a species into the reservoir, the amount of the species within the reservoir, and the flux of the species out of the reservoir.’
    • ‘The model presented here is focused on interpreting the mechanism and resulting dynamics of the solute per se so it will be further assumed that there is no radial flux of solute through the tube walls.’
    • ‘In that case, the Lipobead membrane restricted flux of both calcium and the indicator dye Fluo - 3.’
    • ‘The calculated water flux shows qualitative agreement with experimental findings for water flux through stratum comeum.’
    • ‘Moreover, this isotope could be useful as a tracer of the flux of organic matter in ocean surface waters.’
    • ‘Regardless of the mechanism involved, these studies make it clear that varying the protein levels of EIN3 serves as an important means to control flux through the signalling pathway.’
    • ‘The authors explain that this is an indication of an enhanced metabolic flux through cysteine to glutathione in all groups of transgenic plants.’
    • ‘Studies of contemporary ice sheets show that the pattern of ice flux within ice streams has a profound effect on mass balance, flow configuration and ice divide positions.’
    outflow, outpouring, outflowing, outrush, rush, current, flood, deluge, emission, discharge, issue
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    1. 1.1Medicine An abnormal discharge of blood or other matter from or within the body.
      • ‘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.’
      • ‘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.’
      discharge, outflowing, outpouring, outrush, rush, flood, deluge, issue, spurt, jet, cascade, stream, torrent, gush, outburst
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    2. 1.2archaic Diarrhea or dysentery.
      • ‘Both of them are ill with the flux.’
  • 2Continuous change.

    ‘the whole political system is in a state of flux’
    • ‘The capital is a city in permanent flux like no other, experiencing a constant process of generational and demographic change.’
    • ‘Reynolds agrees that higher education is in a period of flux regarding the issues that are dearest to her heart.’
    • ‘This world is luminous with suffering; everything is fragile, prone to flux.’
    • ‘Caribbean civilization represents the meeting of Old and New Worlds and the freshness of being ever caught up in a creative whirlpool of constant flux.’
    • ‘This time Hearts wanted him, too, but for a man searching for stability, the Tynecastle club's current state of flux must have been disconcerting.’
    • ‘While downtown everything is in flux, in a rush, trying to emulate the fluidity and energy of the West, here everything is tranquil and fixed.’
    • ‘My views on this issue are still in flux, so I'm just going to present a link to this article by Andrew Sullivan without much comment.’
    • ‘Professional golfers in India are going through a period of flux.’
    • ‘The book begins with a re-interpretation of the post-Cold War international system firmly placing the current state of flux and change in an arena of global disorder.’
    • ‘Wolfson, on the other hand, argued that marriage has been in a state of flux throughout American history, and has undergone four major redefinitions in the past century.’
    • ‘Changing business practices leave the communications process in flux.’
    • ‘With youth culture constantly going through a state of flux and change it is a relief to have contemporary specialists to talk with.’
    • ‘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.’
    • ‘Instead we have to appreciate that social order is constantly fluid, ever in flux.’
    • ‘Challenges abound, from a review process still in flux to issues of libel and copyright.’
    • ‘One symptom of the present flux and uncertainty in American life can be found at the box office.’
    • ‘Are there different kinds of roles you play in the creative process, or is that in flux as well?’
    • ‘The industry's current state of flux - some companies losing staff, others recruiting heavily - means that there is now a great deal of potential for building new teams.’
    continuous change, changeability, changeableness, variability, inconstancy, fluidity, instability, unsteadiness, unpredictability, irregularity, fitfulness, unreliability, fickleness
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  • 3Physics
    The rate of flow of a fluid, radiant energy, or particles across a given area.

    • ‘A photodiode is mounted on the integrating sphere to measure the radiant flux from the diode laser entering the sphere.’
    • ‘Why is the solar neutrino flux less than half its expected value?’
    • ‘Plasma membrane stress failure is but one of many stimuli that trigger cell remodeling and thereby mediate changes in fluid flux across the vascular wall.’
    • ‘The energy flux was measured with a short-wave ultraviolet intensity meter (UVP, USA).’
    • ‘Now we use Wien's law to calculate the wavelength of the maximum energy flux for these temperatures.’
    flow, movement, motion, transfer, course, passage, current, drift, circulation, trickle, stream, swirl, surge, sweep, gush, roll, rush, welling, spate, tide
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    1. 3.1The amount of radiation or number of particles incident on an area in a given time.
      • ‘But an increase in light flux did lead to degradation of the dyes.’
      • ‘For the Sun, there is no ambiguity: no such settling could explain the enormous radiated flux of light.’
      • ‘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.’
      • ‘Such a measurement, the fluence rate, is defined as the radiation flux from all directions incident on a small sphere in space.’
      • ‘All fluorescent lamps used as sources for UV-B radiation necessarily emit UV-C, UV-A and a small flux of blue visible radiation.’
    2. 3.2The total electric or magnetic field passing through a surface.
      • ‘If the magnetic flux of the body becomes stronger, cells attract more strongly to each other and therefore create a denser reunion.’
      • ‘Alternatively, actively powered Hall effect sensors can measure the absolute magnetic flux.’
      • ‘The magnetic flux quanta can create specific magnetic profiles within a given sample or device, according to Nori and Savel'ev.’
      • ‘The magnetic flux is measured by external coils, from which the conductivity inside the object can be calculated.’
      • ‘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.’
  • 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.

    • ‘In the case of oxidation-resistant metals the reaction is facilitated by the use of a chemical flux or metal powder.’
    • ‘This problem is particularly acute in the automobile industry where the rosin used in soldering flux, varnishes, lacquers and surface finishes is thought to be a major cause of dermatitis.’
    • ‘Later imitators did produce high temperature ceramics using such fluxes, such as bone porcelain, like Beleek.’
    • ‘In place of the special fluxes a simple mixture of silver chloride and potassium chloride or manganese chloride and potassium chloride is sufficient.’
    • ‘The water acts as a simple flux to lower the melting point of some minerals.’
    1. 4.1A substance added to a furnace during metal smelting or glassmaking that combines with impurities to form slag.
      • ‘These materials are the glass-forming substances, fluxes, stabilizers, and secondary components.’
      • ‘Slaked lime is an important flux in the reduction of iron in blast furnaces.’
      • ‘An amount of flux is added to the crucible and the mixture is fused at high temperature in the furnace.’
      • ‘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.’


  • Treat (a metal object) with a flux to promote melting.

    • ‘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.’
    • ‘Fluorite was not an economic commodity until the advent of modern steel-making processes during the late nineteenth century created a demand for it as a fluxing agent.’
    • ‘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.’
    • ‘The face of the backing would be scoured clean and fluxed.’


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