K Cell

A K cell (aka killer cell) is a lymphocyte[?] with immunoglobulin Fc receptors, which allow it to bind to and kill antibody-coated cells by antibody-dependent cell-mediated cytotoxicity[?] (ADCC). Once bound the cells act like T cells and "program" the target cell to "self-destruct" by apoptosis.

K cells are probably a sub-set of NK cells.