any of the lymphocytes not derived from the thymus, that mature in the bone marrow and help to build antibodies
see also T cell
Word origin
< b(ursa of Fabricius), a structure in birds analogous to the human thymus
B cell in American English
noun Biology
1. Also called: B lymphocyte
a type of lymphocyte, developed in bone marrow, that circulates in the blood and lymph and, upon encountering a particular foreign antigen, differentiates into a clone of plasma cells that secrete a specific antibody and a clone of memory cells that make the antibody on subsequent encounters
2. Also called: beta cell
a cell in the islet of Langerhans that produces and secretes insulin
Word origin
[1970–75; (def. 1) perh. B(one-derived); (def. 2) B(ursa of Langerhans-derived)]