re·​nin ˈrē-nən How to pronounce renin (audio)
: a proteolytic enzyme of the kidney that plays a major role in the release of angiotensin

Examples of renin in a Sentence

Recent Examples on the Web The kidneys respond by secreting a substance, renin, which starts a cascade (the renin-angiotensin system) that causes the blood pressure to go up. Dr. Keith Roach, oregonlive, 8 Sep. 2023 One of the ways the body exerts this control is with a hormone called renin, which makes blood vessels narrower when the pressure needs to be kept up. Quanta Magazine, 30 Nov. 2017 Olfr78, Pluznick and her colleagues discovered, helps drive the production of renin. Quanta Magazine, 30 Nov. 2017 Over the next 15 years, investigations by several groups showed that renin itself did not affect blood vessels, but rather activated a blood protein called angiotensinogen, making angiotensin. Mark C. Fishman, STAT, 7 May 2018 Thirty-six years later, poor blood flow to the kidneys was linked to high blood pressure and release of the protein renin. Mark C. Fishman, STAT, 7 May 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'renin.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


International Scientific Vocabulary, from Latin renes

First Known Use

1903, in the meaning defined above

Time Traveler
The first known use of renin was in 1903

Dictionary Entries Near renin

Cite this Entry

“Renin.” Dictionary, Merriam-Webster, Accessed 25 Apr. 2024.

Medical Definition


ˈrē-nən also ˈren-ən
: a proteolytic enzyme of the blood that is produced and secreted by the juxtaglomerular cells of the kidney and hydrolyzes angiotensinogen to angiotensin I

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