XI /ksaɪ/ ► audio Scrabble 9 Words With Friends 9 Definition adjective being one more than ten. — synonyms: eleven, 11 noun the cardinal number that is the sum of ten and one. — synonyms: eleven, 11 noun the 14th letter of the Greek alphabet. See all 1 words you can make from XI → 2-letter words Words starting with X Words ending with I ← Unscramble different letters