circulatory system

noun

: the system of blood, blood vessels, lymphatics, and heart concerned with the circulation of the blood and lymph

Examples of circulatory system in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
These include tenocytes [the primary component of tendons]; the cells that wrap around blood vessels and stabilize the circulatory system; the smooth muscle cells of the colon; and kidney epithelial cells, which filter toxins from the blood. — Ingrid Wickelgren, Quanta Magazine, 14 Aug. 2026 The Galaxy Watch 9 adds overnight vitals monitoring, plus a new Fitness Index score to evaluate your overall physical state, a new Daily Cardio Load to suggest how hard to work out, and a Heart Health Score for insights into your circulatory system. — Will Greenwald, PC Magazine, 12 Aug. 2026 Unlike your circulatory system, which uses your heart to pump blood through your body, your lymphatic system doesn’t come with an automatic pump to stimulate lymph fluid through your tissues. — Sukhman Rekhi, Verywell Health, 10 Aug. 2026 Meanwhile, if Johnson is the heart of AC/DC, Young remains its circulatory system. — Théoden Janes, Charlotte Observer, 22 July 2026 See All Example Sentences for circulatory system

Word History

First Known Use

1862, in the meaning defined above

Time Traveler
The first known use of circulatory system was in 1862

Rhymes for circulatory system

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Browse Nearby Words

circulatory
circulatory system
circulus in definiendo
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Cite this Entry

“Circulatory system.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/circulatory%20system. Accessed 21 Aug. 2026.

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Kids Definition

circulatory system

noun
: the bodily system of blood, vessels, and heart concerned with the circulation of the blood and lymph

Medical Definition

circulatory system

noun
: the system of blood, blood vessels, lymphatics, and heart concerned with the circulation of the blood and lymph

More from Merriam-Webster on circulatory system

Britannica.com: Encyclopedia article about circulatory system

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