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

After tying or plugging up the holes in the sides of the artery, pour water into the small end and observe the closing of the semilunar valve.

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