A type of white blood cell white blood cell: Cells in the body that fight disease and infection by attacking and killing germs. There are several types of white blood cells including neutrophils, eosinophils, basophils, lymphocytes and monocytes. Each type of cell fights a different kind of germ. Also called WBC, leukocyte. . B lymphoctyes, or B cells, help make special proteins called antibodies that fight bacteria and viruses (immune response). T lymphocytes, or T cells, help kill tumor cells and help the body's immune response.
