[ fluhks ]
See synonyms for: fluxfluxedfluxing on Thesaurus.com

  1. a flowing or flow.

  2. the flowing in of the tide.

  1. continuous change, passage, or movement: His political views are in a state of flux.

  2. Physics.

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

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

  3. Chemistry, Metallurgy.

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

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

    • (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.

verb (used with object)
  1. to melt; make fluid.

  2. to fuse by the use of flux.

  1. Obsolete. to purge.

verb (used without object)
  1. to flow.

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

Other words for flux

Other words from flux

  • non·flux, noun
  • su·per·flux, noun
  • trans·flux, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use flux in a sentence

British Dictionary definitions for flux


/ (flʌks) /

  1. a flow or discharge

  2. continuous change; instability

  1. 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

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

  3. a similar substance used in the making of glass

  4. physics

    • 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)

    • 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

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

  6. the act or process of melting; fusion

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

  1. to make or become fluid

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

  1. (tr) an obsolete word for purge

Origin of flux

C14: from Latin fluxus a flow, from fluere to flow

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for flux


[ 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. See also field magnetic flux.

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

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

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

  4. 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.

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

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.