| any of various nearly colorless cells of the immune system that circulate mainly in the blood and lymph and participate in reactions to invading microorganisms or foreign particles, comprising the B cells, T cells, macrophages, monocytes, and granulocytes. |
Colorless cells in the blood that help combat infection. Some white blood cells act as scavengers by engulfing foreign particles (such as bacteria) and destroying them. Others produce antibodies or destroy dead cells. (See AIDS.)
white blood cell n.
Abbr. WBC
Any of the colorless or white cells in the blood that have a nucleus and cytoplasm and help protect the body from infection and disease through specialized neutrophils, lymphocytes, and monocytes. Also called leukocyte, white corpuscle.
