M

M is a letter of the Latin (Roman) alphabet, the script now used to write English and most languages of western Europe and, today, much of the world. It represents /m/. Historically it is from Phoenician mem ('water') by way of Greek mu. Unlike the Hebrew and Greek alphabets, the Latin (Roman) alphabet never developed a systematic per-letter mystical or numerological tradition: Roman numerals form a separate, non-alphabetic system, so this entry stays with the letter's linguistic and historical record. The Roman alphabet is the youngest of the three historical scripts covered in this atlas: Latium adapted it around the 7th century BCE from a west Greek alphabet, reaching it through Etruscan intermediaries who had themselves taken their letters from Greek colonists settled in the bay of Naples. Latin calls each letter simply by its sound rather than by an inherited name, unlike Hebrew and Greek, and it never built an alphabetic numeral system of its own, so there is no ancient Latin counterpart to Hebrew gematria or Greek isopsephy; Roman numerals are a separate, non-alphabetic notation.

A modern practice called name numerology, drawn from a twentieth-century repeating 1-to-9 chart and commonly marketed as Pythagorean despite no documented link to Pythagoras, assigns the letter M the digit 4; a rival popular scheme, the so-called Chaldean system, assigns different digits to the same letters, so even the two modern schemes disagree with each other.

This atlas covers the Latin M's phonetic descent from Phoenician mem through Greek mu elsewhere. Graphically, mem's wavy water-sign straightened over the alphabet's Greek and Etruscan transmission into a letter built from vertical strokes; the number of strokes forming its middle section varied between three and four in different ancient scripts before Roman usage settled on the familiar four-stroke, W-topped capital M used today, with the lowercase m simply a smaller, rounder version of the same structure fixed by medieval cursive hands. Separately, M is one of seven Latin letters also used as a Roman numeral, standing for one thousand, the largest of the standard set.

M's numeral value is often explained as reinforced, if not directly caused, by its being the first letter of the Latin word mille, thousand, though scholars of the numeral system note this may be a later folk association layered onto a symbol whose graphic origin, like several of the larger Roman numerals, is not fully settled; some accounts derive the numeral shape from an earlier non-alphabetic mark only later assimilated to the letter M. As with the other numeral letters, this value is a separate notational system from the alphabet's phonetic and mystical traditions and carries no comparable esoteric weight of its own.