back·​flow | \ ˈbak-ˌflō How to pronounce backflow (audio) \

Definition of backflow

: a flowing back or returning especially toward a source

Examples of backflow in a Sentence

Recent Examples on the Web

Calcium deposits in heart valves lead to scarring that can restrict outflow and allow backflow. WSJ, "Cardiovascular Health Frontier Is Calcium," 8 Oct. 2018 Keep in mind that some kits don’t include pressure regulators, timers, backflow preventers, and line filters. The Editors, Good Housekeeping, "How to Install a Drip Irrigation System in Your Garden," 17 July 2018 The city plans to build a new pumping station to prevent backflow from storm drains, which sends water into the streets. Talia Richman,, "Annapolis Boat Show will 'rise above' after flooding during last year's event," 7 July 2018 Keep in mind that some kits don’t pressure regulators, timers, backflow preventers, and line filters. The Editors Of Organic Life, Good Housekeeping, "How To Use Soaker Hoses To Install A Drip Irrigation System In Your Garden," 7 Mar. 2017 Its closed system uses a thin rubber backflow protector as a membrane to shield the tubing and pumping mechanism from possible milk-splashing, which could threaten the milk’s sterility. Adrienne So, WIRED, "Which Breast Pump Is Right For Me?," 8 Apr. 2018 The backflow also temporarily created the tallest waterfall recorded in the state of Louisiana, at 150 to 164 feet, depending on the source. Kelly Kazek |,, "Where does Alabama's Golly Hole rank among country's largest sinkholes?," 11 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'backflow.' 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 backflow

1878, in the meaning defined above

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Time Traveler for backflow

The first known use of backflow was in 1878

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More from Merriam-Webster on backflow

Rhyming Dictionary: Words that rhyme with backflow

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characterized by aphorism

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