Englishquantum chromodynamics /ˈkwän(t)əm ˌkrōmōdīˈnamiks, ˈkwɑn(t)əm ˌkroʊmoʊdaɪˈnæmɪks/ (abbreviation QCD)
▸ plural noun [treated as singular] Physics a quantum field theory in which the strong interaction is described in terms of an interaction between quarks mediated by gluons, both quarks and gluons being assigned a quantum number called “color.”.