re·​flux | \ ˈrē-ˌfləks How to pronounce reflux (audio) \

Definition of reflux

 (Entry 1 of 2)

1a : a flowing back
2 : a process of refluxing or condition of being refluxed


re·​flux | \ ri-ˈfləks How to pronounce reflux (audio) , 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 syrups were supposed to include the drug omeprazole, a common drug to treat acid reflux. Beth Mole, Ars Technica, "Hairy “werewolf syndrome” in babies and kids caused by drug mix-up," 29 Aug. 2019 Spicy and acidic foods can also aggravate acid reflux and indigestion, per the NIDDK. Carolyn L. Todd, SELF, "Is Late-Night Snacking Really So Wrong?," 23 Aug. 2019 That, and medication for acid reflux, made Chayton a much happier baby. Alix Boyle,, "Babies learning sign language: Promotes communication, bonding and verbal skills," 16 July 2019 But the team’s earned run average this year is acid reflux-inducing 5.10, which ranks dead last in the National League. Mark Kiszla, The Denver Post, "Kiszla: All-star David Dahl a smash hit for Rockies, but can Blake Street Bombers 2.0 slug their way to playoffs?," 30 June 2019 Vinegar contains zero calories, enhances flavor, and poses a low health risk, except for acid reflux-sufferers and diabetics. Jaclyn London, Ms, Rd, Cdn, Good Housekeeping, "The Real Benefits of Apple Cider Vinegar, According to a Nutritionist," 21 Nov. 2018 Then head to your doctor, as bad breath could be a symptom of various medical conditions such as sinus or lung infections, bronchitis, gastric reflux, a tonsil infection, and even some liver or kidney diseases. Samantha Lefave, Redbook, "Why You Should Never Ignore Sweet-Smelling Urine (or These Other Body Odors)," 3 Aug. 2018 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 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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Statistics for reflux

Last Updated

7 Sep 2019

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Time Traveler for reflux

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

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More Definitions for reflux



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 How to pronounce reflux (audio) \

Medical Definition of reflux

 (Entry 1 of 3)

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

Rhyming Dictionary: Words that rhyme with reflux Encyclopedia article about reflux

Comments on reflux

What made you want to look up reflux? Please tell us where you read or heard it (including the quote, if possible).


recurring in steady succession

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