sinus node
noun
: a small mass of tissue that is embedded in the musculature of the right atrium of higher vertebrates and that originates the impulses stimulating the heartbeat
Examples of sinus node in a Sentence
Recent Examples on the Web
Hearts beat when the sinus node, a small mass of tissue in the right upper chamber, transmits an impulse to the heart cells.
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Michael Ciaglo, National Geographic, 5 June 2020
Over the course of a day, a person’s heart beats about 100,000 times, and each beat begins with an electrical signal generated in the sinus node in the heart’s upper right chamber.
—Emily Sohn, Washington Post, 7 Mar. 2018
Michael Ciaglo, National Geographic, 5 June 2020
Over the course of a day, a person’s heart beats about 100,000 times, and each beat begins with an electrical signal generated in the sinus node in the heart’s upper right chamber.
—Emily Sohn, Washington Post, 7 Mar. 2018
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'sinus node.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
First Known Use
1937, in the meaning defined above
Dictionary Entries Near sinus node
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“Sinus node.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sinus%20node. Accessed 18 Apr. 2024.
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Medical Definition
sinus node
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