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 of flux

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

New products on the market With the introduction of nicotine vapes in the early 2010s and, more recently, nicotine pouches in the mid-2010s, the tobacco and nicotine market has been in flux. — Jamie Hartmann-Boyce, The Conversation, 17 Aug. 2026

Though current guidance on adverse action notices are in flux, a borrower should still not assume the algorithm’s answer is final. — Terdawn Deboe, Forbes.com, 15 Aug. 2026

Verb

Then he was put on waivers by the Utah Mammoth in September and dealt to Edmonton in December, his career still flux. — Joe Smith, New York Times, 31 Jan. 2026

The technology uses the slag to combine it with fluxing agents. — Noël Fletcher, Forbes.com, 5 Sep. 2025

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