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Medical Dictionary

sinoatrial node

noun

Medical Definition of sinoatrial node

  1. :  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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a division or portion of a pool or whole

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