archaeornithes Archaeornis • Archaeornithes · · · Info · Definitions · Characters · · archaeornithes · · Text Latin · · Script 14 · · Length 5 · · Syllables Definitions · · · (noun) primitive reptile-like fossil birds of the Jurassic or early Cretaceous. Synonyms: Archaeornithes, subclass Archaeornithes. · · Noun Definition 1 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 n latin small letter n U+006E 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