Rheiformes Rheidae • rhein · · · Info · Definitions · Characters · · Rheiformes · · Text Latin · · Script 10 · · Length Definitions · · · (noun) a ratite bird order: birds intermediate in characteristics between ostriches and emus: recent and extinct rheas. Synonyms: order Rheiformes. · · Noun Definition 1 Characters · · R latin capital letter r U+0052 e latin small letter e U+0065 f latin small letter f U+0066 h latin small letter h U+0068 i latin small letter i U+0069 m latin small letter m U+006D o latin small letter o U+006F r latin small letter r U+0072 s latin small letter s U+0073