re·flux | \ˈrē-ˌfləks \

Definition of reflux 

(Entry 1 of 2)

1a : a flowing back

b : gastroesophageal reflux

2 : a process of refluxing or condition of being refluxed


re·flux | \ri-ˈfləks, ˈrē-ˌfləks\
refluxed; refluxing; refluxes

Definition of reflux (Entry 2 of 2)

transitive verb

: to cause to flow back or return especially : to heat such that the vapors formed condense and return to be heated again

intransitive verb

: to flow back

Examples of reflux in a Sentence

Recent Examples on the Web: Noun

The drugs studied were those commonly taken by adults for high blood pressure, acid reflux, pain, and birth control, among others (the authors were careful to exclude adults who were already taking antidepressant medications). Ronald S. Litman,, "Unintended consequences of taking prescription medicines," 20 June 2018 Dental erosion usually happens when too much acid (like from soda, acid reflux, or excessive vomiting damages your teeth over time, the ADA says. Korin Miller, SELF, "5 Reasons Your Teeth Are So Agonizingly Sensitive," 18 Apr. 2018 Acid reflux comes from a diet that is high in sugar. Naseem S. Miller,, "Your child's runny nose may be because of acid reflux," 30 May 2018 The bacteria have been found in the plaque on people’s teeth, carried there by refluxes into their mouths. Carl Zimmer, STAT, "Shot through with microbes: How our bodies adapt to a hidden world of bacteria," 30 May 2018 By her second birthday, Mimi had outgrown the reflux. Sandra G. Boodman, Washington Post, "Why did a little girl have a persistent ‘smoker’s cough’?," 31 Mar. 2018 Click to Read Story A Surprise Medical Solution: Hypnosis Major hospitals are finding hypnotherapy can help sufferers of digestive conditions like heartburn, acid reflux and irritable bowel syndrome. Sumathi Reddy, WSJ, "From Meditation to Medication: Headspace Has a Prescription Strategy," 25 June 2018 The most common of them are drugs such as hormonal birth control, beta-blockers (used for conditions such as high blood pressure, heart attacks, and migraines), and proton-pump inhibitors (used for acid reflux). Beth Mole, Ars Technica, "Common drugs have depression as a possible side effect—a third of us take them," 15 June 2018 French’s medical issues included sleep apnea, high blood pressure and acid reflux, family members said. Katy Moeller, idahostatesman, "Family of missing Boise man says sheriff notified them of human bone found in river," 6 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reflux.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of reflux


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


1926, in the meaning defined at transitive sense

History and Etymology for reflux


Middle English, from Medieval Latin refluxus, from Latin re- + fluxus flow — more at flux

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The first known use of reflux was in the 15th century

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English Language Learners Definition of reflux

medical : a backward flow of the contents of the stomach into the esophagus that causes heartburn


re·flux | \ˈrē-ˌfləks \

Medical Definition of reflux 

(Entry 1 of 3)

1a : a flowing back : regurgitation reflux of gastric acid mitral valve reflux

b : gastroesophageal reflux

2 : a process of refluxing or condition of being refluxed the sample was hydrolyzed…under reflux for 24 hours— T. Y. Ho et al



Medical Definition of reflux (Entry 2 of 3)

: of, relating to, involving, or caused by reflux reflux esophagitis

Medical Definition of reflux (Entry 3 of 3)

: to cause to flow back or return especially : to heat (as under a reflux condenser) so that the vapors formed condense to a liquid that flows back to be heated again

intransitive verb

: to flow back damage to the esophageal mucous membrane when gastric acid refluxed into the esophagus

More from Merriam-Webster on reflux

See words that rhyme with reflux Encyclopedia article about reflux

Comments on reflux

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