Gnathostomata Gnathostoma • gnathostomatous · · · Info · Definitions · Characters · · Gnathostomata · · Text Latin · · Script 13 · · Length Definitions · · · (noun) comprising all vertebrates with upper and lower jaws. Synonyms: superclass Gnathostomata. · · Noun Definition 1 Characters · · G latin capital letter g U+0047 a latin small letter a U+0061 h latin small letter h U+0068 m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F s latin small letter s U+0073 t latin small letter t U+0074