Osteostraci osteostracan • osteosuture · · · Info · Definitions · Characters · · Osteostraci · · Text Latin · · Script 11 · · Length Definitions · · · (noun) extinct group of armored fish-like vertebrates; taxonomy is not clear. Synonyms: suborder Osteostraci, Cephalaspida, suborder Cephalaspida. · · Noun Definition 1 Characters · · O latin capital letter o U+004F a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 o latin small letter o U+006F r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074