semilunar

American  

[sem-ee-loo-ner, sem-ahy-] / ˌsɛm iˈlu nər, ˌsɛm aɪ- /

adjective

1. shaped like a half-moon; crescent.

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semilunar British  

/ ˌsɛmɪˈluːnə /

adjective

1. shaped like a crescent or half-moon

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Other Word Forms

• presemilunar
  adjective

Etymology

Origin of semilunar

First recorded in 1590–1600; semi- + lunar

Example Sentences

Both the aortic and the pulmonary valves are semilunar valves.

From Textbooks • Jun. 9, 2022

Any condition that increases resistance requires a greater afterload to force open the semilunar valves and pump the blood.

From Textbooks • Jun. 19, 2013

The second heart sound, S2 or dub, occurs when the semilunar valves close.

From Textbooks • Jun. 19, 2013

As pressure in the ventricles rises above two major arteries, blood pushes open the two semilunar valves and moves into the pulmonary trunk and aorta in the ventricular ejection phase.

From Textbooks • Jun. 19, 2013

The tricuspid valves had lost their smoothness and transparency; the semilunar valves of the pulmonary artery were cartilaginous at their bases.

From Cases of Organic Diseases of the Heart by Warren, John Collins