cytokine cytoid • cytokinesis · · · Info · Definitions · Characters · · cytokine · · Text Latin · · Script 8 · · Length 3 · · Syllables Definitions · · · (noun) any of various protein molecules secreted by cells of the immune system that serve to regulate the immune system. · · Noun Definition 1 Characters · · c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 k latin small letter k U+006B n latin small letter n U+006E o latin small letter o U+006F t latin small letter t U+0074 y latin small letter y U+0079