immunogen immunochemistry • immunogenetic · · · Info · Definitions · Synonyms · Characters · · immunogen · · Text Latin · · Script 9 · · Length Definitions · · · (noun) any substance or organism that provokes an immune response (produces immunity) when introduced into the body. Synonyms: immunizing agent. · · Noun Definition 1 Synonyms · · · immunizing agent · · Synonym 1 Characters · · e latin small letter e U+0065 g latin small letter g U+0067 i latin small letter i U+0069 m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F u latin small letter u U+0075