t-cell meaning

noun
  A type of lymphocyte involved in cellular immunity that matures (in mammals) in the thymus gland, eg a cytotoxic T-cell able to kill virus-infected cells

[Medicine]
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES,CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES,HELPER-INDUCER). They are formed when lymphocytes circulate through the thymus gland and differentiate to thymocytes. When exposed to an antigen,they divide rapidly and produce large numbers of new T cells sensitized to that antigen.