sinoatrial node


Definition of sinoatrial node

First Known Use of sinoatrial node

1913, in the meaning defined above

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The first known use of sinoatrial node was in 1913

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Cite this Entry

“Sinoatrial node.” Dictionary, Merriam-Webster, Accessed 28 Oct. 2020.

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sinoatrial node


Medical Definition of sinoatrial node

: a small mass of tissue that is made up of Purkinje fibers, ganglion cells, and nerve fibers, that is embedded in the musculature of the right atrium of higher vertebrates, and that originates the impulses stimulating the heartbeat

called also S-A node, sinus node

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