catholicos catholicon • catholicus · · · Info · Definitions · Characters · · catholicos · · Text Latin · · Script 10 · · Length Definitions · · · (noun) the ecclesiastical title of the leaders of the Nestorian and Armenian churches. Synonyms: Catholicos. · · Noun Definition 1 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 h latin small letter h U+0068 i latin small letter i U+0069 l latin small letter l U+006C o latin small letter o U+006F s latin small letter s U+0073 t latin small letter t U+0074