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

"Maybe there's a bit more acid reflux and arthritis," he joked.

From BBC • Mar. 1, 2026

Cowell deemed this acid reflux extravaganza to be “small.”

From Salon • May 31, 2025

That includes the vast majority of people with acid reflux.

From Los Angeles Times • Sep. 16, 2024

But the highest tide has its ebb; and in all things of this kind there is a reflux which sometimes, also, is more impetuously violent than the first aggression.

From The Fortunate Mistress (Parts 1 and 2) or a History of the Life of Mademoiselle de Beleau Known by the Name of the Lady Roxana by Defoe, Daniel