Platelet: An irregular, disc-shaped element in the blood that assists in blood clotting. During normal blood clotting, the platelets clump together (aggregate). Although platelets are often classed as blood cells, they are actually fragments of large bone marrow cells called megakaryocytes.
CONTINUE SCROLLING OR CLICK HERE FOR RELATED SLIDESHOW
SLIDESHOW
Heart Disease: Causes of a Heart Attack See SlideshowHealth Solutions From Our Sponsors
Last Editorial Review: 12/27/2018