xxi xxc • xxii · · · Info · Definitions · Synonyms · Characters · · xxi · · Text Latin · · Script 3 · · Length 1 · · Syllables Definitions · · · (noun) the cardinal number that is the sum of twenty and one. Synonyms: twenty-one, 21, XXI. · · Noun Definition 1 (adj) being one more than twenty. Synonyms: twenty-one, 21. · · Adjective Definition 1 Synonyms · · · twenty-one · · Synonym 1 21 · · Synonym 2 Characters · · i latin small letter i U+0069 x latin small letter x U+0078