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

An electrical impulse is sent from the sinus node in the region at the top of the heart down through the bottom to make the heart muscle contract. —Julie Scott, Msn, Anp-Bc, Aocnp, Verywell Health, 23 Oct. 2024

This indicates the sinus node is not working properly. —Angela Ryan Lee, Verywell Health, 25 Sep. 2024

Normally, specialized cells called the sinus node in the heart's upper right chamber give a rhythmic signal for the heart to contract. —Christopher Lee, Verywell Health, 22 July 2024

Hearts beat when the sinus node, a small mass of tissue in the right upper chamber, transmits an impulse to the heart cells. —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

Word History

First Known Use

1937, in the meaning defined above

Medical Definition

sinus node

noun

: sinoatrial node