What does sickle shape mean?

A sickle shape refers to a curved, crescent-like form that resembles the tool used for cutting grain. In medical contexts, it often describes the shape of red blood cells in sickle cell disease, where abnormal hemoglobin causes the cells to become rigid and crescent-shaped, leading to various health complications. This sickle shape contrasts with the typical disc-shaped appearance of healthy red blood cells.