History, etymology, and pronunciation of m, the thirteenth letter in the alphabet. It corresponds to the Semitic mem and to the Greek mu. The Semitic form may derive from an earlier sign representing waves of water. The sound represented by the letter has been from the beginning the labial nasal., In calendars, M sometimes means Monday or means one of the months "March" or "May". In money, M means million, such as $25M (twenty-five million dollars). In the SI, m is the symbol for the metre. In Roman numerals, M means one thousand. M is also the name of a 1930 German movie made by Fritz Lang and its 1951 remake., This letter M video by ABCmouse is full of marvelous messages that help children master learning both upper and lower case letter M., The complete list of text M Symbols, copy and paste these M letter text symbols to use and share anywhere you want., M, or m, is the thirteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of several western European languages and others worldwide. Its name in English is em (pronounced / ˈɛm / ⓘ), plural ems. [1], M meaning: 1 : the 13th letter of the English alphabet; 2 : the Roman numeral that means 1,000.