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semilunar valve

noun

Definition of semilunar valve

  1. :  any of the crescent-shaped cusps that occur as a set of three between the heart and the aorta and another of three between the heart and the pulmonary artery, are forced apart by pressure in the ventricles during systole and pushed together by pressure in the arteries during diastole, and prevent regurgitation of blood into the ventricles; also :  either set of three cusps



Circa 1719

First Known Use of semilunar valve

circa 1719


Medical Dictionary

semilunar valve

noun

Medical Definition of semilunar valve

  1. 1:  either of two valves of which one is situated at the opening between the heart and the aorta and the other at the opening between the heart and the pulmonary artery, which prevent regurgitation of blood into the ventricles, and each of which is made up of three crescent-shaped cusps that are forced apart by pressure in the ventricles exerted during systole and are pushed together by pressure in the arteries exerted during diastole

  2. 2:  semilunar cusp




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