Crossword clues for the word: MACHNUMBER The word MACHNUMBER has appeared as an answer to at least 2 crossword clues on different crossword puzzles. Crossword clues for MACHNUMBER Showing 1 to 2 of 2 results Clue(s) "Measure of speed, in the jet age." It indicates how many times you'll be made fun of after doing something dumb?