semilunar valves
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Related to semilunar valves: cardiac cycle, tricuspid valve
semilunar valves
The crescent-shaped valves, each having three cusps, situated one at the beginning of the AORTA and the other at the origin of the PULMONARY ARTERY. These valves allow blood to flow only in a direction away from the heart.Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005