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

The openings of the arteries behind the semilunar valves may be very small.

From Project Gutenberg

The thoracic duct is equal in diameter to a goose-quill, and, at its termination, is provided with a pair of semilunar valves, which prevent the admission of venous blood into its cylinder.

From Project Gutenberg

The semilunar valves of the pulmonary artery and aorta were unusually small, and their bases cartilaginous.

From Project Gutenberg

Just under the mucous membrane covering the anal columns and semilunar valves is the fatty tissue forming a bed upon which the mucous membrane rests.

From Project Gutenberg

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

From Project Gutenberg