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 Dozens of legal drugs are also well documented for triggering false-positive drug screens, from antihistamines to attention deficit disorder medication, acid reflux pills to blood pressure pills and even ibuprofen. Anna Claire Vollers |, al, "New moms in Alabama face suspicion over error-prone drug screens," 9 Feb. 2020 Last year, Adam Clark-Joseph, cofounder of the mail order pharmacy Valisure, ordered ranitidine syrup, prescribed to treat reflux in his infant daughter. Michele Cohen Marill, Wired, "The FDA Announces Two More Antacid Recalls Due to Cancer Risk," 10 Jan. 2020 This can cause acid reflux, meaning that gastric acid can enter your esophagus and lead to heartburn. Tara C. Smith, SELF, "Should You Worry About the Zantac Recall If You've Been Using It for Heartburn?," 31 Oct. 2019 He is being treated for an irregular heartbeat, high cholesterol, acid reflux, and seasonal allergies. Emily Larsen, Washington Examiner, "Biden acknowledges he might die in office: 'I'm an old guy'," 29 Jan. 2020 Any stress can lead to worsening of underlying GI issues, including acid reflux (indigestion) and other GI issues. Lauren Jarvis-gibson, Teen Vogue, "Physical Symptoms of Anxiety Disorder That You Might Not Recognize," 27 Dec. 2019 That unpleasant burning sensation (and sometimes taste) in your throat and/or chest is known as gastroesophageal reflux (i.e. acid reflux or heartburn). Carolyn L. Todd, SELF, "Is Late-Night Snacking Really So Wrong?," 23 Aug. 2019 Monahan noted that Sanders has previously been treated for gout, high cholesterol, diverticulitis, hypothyroidism, laryngitis secondary to esophageal reflux, lumbar strain, and complete removal of superficial skin lesions. Rebecca Morin, USA TODAY, "Bernie Sanders in 'good health' after heart attack, according to his doctor," 31 Dec. 2019 Biden is taking blood thinners and medication for acid reflux, cholesterol and seasonal allergies. Ben Kamisar, NBC News, "Collins' decision to seek re-election puts her in middle of fight for Senate control," 19 Dec. 2019 Recent Examples on the Web: Verb On recalling Zantac What to do for the fizzle and roil When refluxing guts sour and spoil? Meghana Keshavan, STAT, "2019 in limericks: The highs and lows from the life sciences," 31 Dec. 2019

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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Time Traveler for reflux

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

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Last Updated

23 Feb 2020

Cite this Entry

“Reflux.” Dictionary, Merriam-Webster, Accessed 4 Apr. 2020.

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More Definitions for reflux


How to pronounce reflux (audio)

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

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More from Merriam-Webster on reflux

Thesaurus: All synonyms and antonyms for reflux

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

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