reflux

American  

[ree-fluhks] / ˈriˌflʌks /

noun

1. a flowing back; ebb.

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reflux British  

/ ˈriːflʌks /

verb

1. chem to boil or be boiled in a vessel attached to a condenser, so that the vapour condenses and flows back into the vessel

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noun

1. chem

   1. an act of refluxing

   2. ( as modifier )

      a reflux condenser

2. the act or an instance of flowing back; ebb

Etymology

Origin of reflux

First recorded in 1400–50; late Middle English word from Medieval Latin word refluxus. See re-, flux

Explanation

Use the noun reflux to talk about a medical condition that gives you an acidic taste in your mouth and a burning feeling in your chest. If a patient suffers from reflux, his stomach and esophagus aren't working quite right — they're allowing acid to flow backwards, which results in discomfort and nausea. There are various ailments that can be defined as reflux, including indigestion and heartburn, as well as conditions that affect babies who have trouble swallowing. Another kind of reflux is the tide's ebb, or outward flow. This is the oldest meaning of the word, which comes from the Latin fluxus, "a flowing."

Example Sentences

Between 40 and 70 percent of patients on these drugs report gastrointestinal adverse effects, like acid reflux, chronic diarrhea, and/or constipation.

From Slate • Mar. 22, 2026

Vocal cord injuries are particularly common among older adults, especially those who experience acid reflux or smoke.

From Science Daily • Jan. 2, 2026

Her youngest child is 22 months old and still nursing; he has acid reflux and an allergy to other forms of milk.

From Salon • Oct. 22, 2025

Beth said Riley later recovered, but at six months old, tests discovered his left kidney was scarred, his right had reflux and there were also issues with his bladder.

From BBC • Oct. 25, 2024

This country is so level, that, at some seasons, it is entirely overflowed, which accounts for the periodical influx and reflux of the waters between the Lake of the Hills and the Peace River.

From Voyages from Montreal Through the Continent of North America to the Frozen and Pacific Oceans in 1789 and 1793 Vol. I by Mackenzie, Alexander