leukocyte

n. white blood cell

White blood cells or leukocytes are cells of the immune system which defend the body against both infectious disease and foreign materials. Several different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Leukocytes are found throughout the body, including the blood and lymphatic system.
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Noun
1. blood cells that engulf and digest bacteria and fungi; an important part of the body's defense system
(synonym) leucocyte, white blood cell, white cell, white blood corpuscle, white corpuscle, WBC
(hypernym) blood cell, blood corpuscle, corpuscle
(hyponym) myelocyte

[LOO-ko-site]
A white blood cell. Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infection and other diseases.

Any of a class of colorless blood cells whose function is to counteract infection.