platelet

Everyday

A tiny piece in your blood that helps it clot (go thick and sticky) to stop bleeding when you are cut. tree →

In the lessons

In science lessons about the body, blood is made of plasma, red blood cells, white blood cells and platelets. Platelets rush to a cut and stick together to make a plug, which becomes a scab. In hospital stories a "platelet count" is checked; people can donate platelets.

Examples

• Platelets help your blood clot when you cut your finger. tree →
• Blood is made of plasma, red cells, white cells and platelets. tree →
• The scab on your knee started with platelets sticking together. tree →
• The doctor checked her platelet count. tree →
• Platelets are much smaller than red blood cells. tree →
• Some people donate platelets to help patients in hospital. tree →

Note

Countable: a platelet, platelets; usually used in the plural. The word means "little plate" because of their flat shape. Platelets are not full cells; they are fragments of bigger cells.