hairy cell leukemia

Definition of hairy cell leukemia
National Cancer Institute

hairy cell leukemia

(HAYR-ee sel loo-KEE-mee-uh)
A rare type of leukemia in which abnormal B-lymphocytes (a type of white blood cell) are present in the bone marrow, spleen, and peripheral blood. When viewed under a microscope, these cells appear to be covered with tiny hair-like projections.

Source: NCI Dictionary of Cancer Terms