ˌsē(ˌ)dēˈāt noun
( -s )
Usage: often attributive
Etymology: c luster of d ifferentiation antigen + 8
: a glycoprotein found on the surface especially of killer T cells that usually functions to facilitate recognition by killer T cell receptors of antigens complexed with molecules of a class that are found on the surface of most nucleated cells and are the product of genes of the major histocompatibility complex