semilunar valve

American  

noun

Anatomy.

1. either of two valves, one in the aorta and one in the pulmonary artery, consisting of a set of three crescent-shaped flaps of tissue and serving to prevent blood from flowing back into the heart after contraction.

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semilunar valve British  

noun

1. anatomy either of two crescent-shaped valves, one in the aorta and one in the pulmonary artery, that prevent regurgitation of blood into the heart

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Etymology

Origin of semilunar valve

First recorded in 1710–20

Example Sentences

There are three dilations in the wall of the aorta just superior to the aortic semilunar valve.

From Textbooks • Jun. 19, 2013

The pulmonary valve is located at the base of the pulmonary trunk, and the left semilunar valve is located at the base of the aorta.

From Textbooks • Jun. 19, 2013

At the base of the pulmonary trunk is the pulmonary semilunar valve, which prevents backflow of blood into the right ventricle during ventricular diastole.

From Textbooks • Jun. 19, 2013

At the base of the aorta is the aortic semilunar valve that prevents backflow of blood into the left ventricle while the heart is relaxing.

From Textbooks • Jun. 19, 2013

The right semilunar valve is situated around the opening of the right ventricle into the pulmonary artery.

From Physiology and Hygiene for Secondary Schools by Walters, Francis M.