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semilunar valve

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.
Compare aortic valve, pulmonary valve.

Origin of semilunar valve

First recorded in 1710–20
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for semilunar valve

semilunar valve

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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
semilunar valve in Medicine

semilunar valve

n.
  1. One of three semilunar segments serving as the cusps of a valve preventing regurgitation, as in the aortic valve and the pulmonary valve.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.