flux

1 of 2

noun

ˈfləks 

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

4

a

: 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

flux

2 of 2

verb

fluxed; fluxing; fluxes

transitive verb

1

: to cause to become fluid

2

: to treat with a flux

intransitive verb

: to become fluid : fuse

Synonyms

Noun

• fluctuation
• oscillation

Verb

• melt
• thaw

Examples of flux in a Sentence

Noun

the English language is always in a state of flux

January typically brings a great flux of returns to department stores.

Verb

a solid will flux more quickly under pressure

Recent Examples on the Web

Noun

For the class of 2025, the promise of the cap and gown is colliding with the unfortunate realities of a labor market in flux. —Hugh Cameron, MSNBC Newsweek, 4 Sep. 2025

Over time, the gamma-ray flux from the Moon fluctuates by about 20% due to these periodic changes in the Sun’s magnetic field. —Ethan Siegel, Big Think, 4 Sep. 2025

Verb

Teams can use real-time dashboards to highlight anomalies, flux analysis results or unexpected movements in accounts and to log all reviewer comments and actions in the system for a clean audit trail. —Shagun Malhotra, Forbes.com, 21 Aug. 2025

Those signs can flux when sleep deprived, traveling or stressed at work as well. —Sandee Lamotte, CNN, 31 Jan. 2020

Word History

Etymology

Noun and Verb

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

First Known Use

Noun

14th century, in the meaning defined at sense 1

Verb

15th century, in the meaning defined at transitive sense 1

Phrases Containing flux

• luminous flux
• magnetic flux
• radiant flux

Rhymes for flux

• chucks
• crux
• ducks
• dux
• klux
• lux
• plucks
• recce
• shucks
• sucks
• trucks
• tucks

Kids Definition

flux

1 of 2 noun

ˈfləks 

1

a

: a flowing in

flux of the tide

b

: a series of changes : a state of continuous change

2

: a substance used to aid the melting or joining (as by removing impurities) of metals or minerals

flux

2 of 2 verb

1

: to become or cause to become fluid : fuse

2

: to treat with a flux

Medical Definition

flux

noun

ˈfləks 

1

a

: 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