M

1.
n. (pl. Ms or M's)
1 the thirteenth letter of the alphabet.
2 (as a Roman numeral) 1,000.
2.
abbr. (also M.)
1 Master.
2 (in titles) Member of.
3 Monsieur.
4 (in the UK in road designations) motorway.
5 mega-.
6 Chem. molar.

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M

(ɛm)

the thirteenth letter of the modern and twelfth of the ancient Roman alphabet, represents historically the Greek mū and the Semitic mēm. The Phœnician form of the letter is