platelet

n. small cytoplasmic body in the blood that aids in clotting, blood platelet

Platelets, or thrombocytes, are the cell fragments circulating in the blood that are involved in the cellular mechanisms of primary hemostasis leading to the formation of blood clots. Dysfunction or low levels of platelets predisposes to bleeding, while high levels, although usually asymptomatic, may increase the risk of thrombosis. An abnormality or disease of the platelets is called a thrombocytopathy.
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Noun
1. tiny bits of protoplasm found in vertebrate blood; essential for blood clotting
(synonym) blood platelet, thrombocyte
(hypernym) protoplasm, living substance

[PLATE-let]
A type of blood cell that helps prevent bleeding by causing blood clots to form. Also called a thrombocyte.

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