Crossword clues for the word: MCLX The word MCLX has appeared as an answer to at least 5 crossword clues on different crossword puzzles. Crossword clues for MCLX Showing 1 to 5 of 5 results Clue(s) 1160. 12th cent. date CCXC quadrupled CXVI x X Year in the 12th century.