<p><strong>Noun:</strong></p><ul><li>a puzzling or inexplicable occurrence or situation: His disappearance is an enigma that has given rise to much speculation.</li><li>a person of puzzling or contradictory character: To me, he has always been an enigma, one minute completely insensitive, the next moved to tears.</li><li>a saying, question, picture, etc., containing a hidden meaning; riddle.</li><li>(initial capital letter) a German-built enciphering machine developed for commercial use in the early 1920s and later adapted and appropriated by German and other Axis powers for military use through World War II.</li></ul>