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White upper layer of blood clot.

Buff-colored stratum on the surface of a blood-clot.

The upper layer of the clot that forms in blood from an individual affected with acute inflammation. Its buff color is owing to the absence of red corpuscles, they having sunk to the lower portions before coagulation began. A more or less marked buffy coat often forms in any blood that coagulates tardily.

See under coat.

(Med.) On blood drawn in a diseased condition, a crust of greyish corpuscles, the red particles sinking.