ef·​flux ˈe-ˌfləks How to pronounce efflux (audio)
: something given off in or as if in a stream
: a passing away : expiration
effluxion noun

Examples of efflux in a Sentence

Recent Examples on the Web The drugs also caused the bacteria to express more efflux pump proteins that shunt antibiotics out of the cell. Diana Gitig, Ars Technica, 26 Jan. 2023 This type of antibiotic efflux is a common problem with the tetracycline antibiotics, often used to treat infections like urinary tract infections, chlamydia and acne. Bill Sullivan, Discover Magazine, 3 Nov. 2021 The compound found in Sichuan peppercorns trigger somatosensory neurons to prevent the influx and efflux of electrolytes, Na^+ and K^+, through ion channels [6,7]. Anthony Martin, Discover Magazine, 13 Jan. 2016 The aviation slowdown during the Covid-19 pandemic, which largely grounded air travel, likely resulted in a surge of insect activity, given that there was less noise and jet efflux to deter insects, the regulators found. Mike Cherney, WSJ, 23 Nov. 2022 The virus Chan selected latches on to what is known as an efflux pump on the bacterial cell wall. Charles Schmidt, Scientific American, 1 Nov. 2019 Zwicker discovered that this chemical influx and efflux will exactly counterbalance each other when an active droplet reaches a certain volume, causing the droplet to stop growing. Quanta Magazine, 19 Jan. 2017 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'efflux.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Medieval Latin effluxus, from effluere

First Known Use

1647, in the meaning defined at sense 1

Time Traveler
The first known use of efflux was in 1647

Dictionary Entries Near efflux

Cite this Entry

“Efflux.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/efflux. Accessed 27 Feb. 2024.

Medical Definition


ef·​flux ˈef-ˌləks How to pronounce efflux (audio)
: something that is given off in or as if in a stream
the red-blood-cell sodium ion efflux
: the action or process of flowing or seeming to flow out
the uptake and efflux of sodium ions

More from Merriam-Webster on efflux

Last Updated: - Updated example sentences
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