The letter M is derived from the Phoenician Mem, via the Greek Mu (Μ,μ). Semitic Mem is most likely derived from a " Proto-Sinaitic" ( Bronze Age) adoption of the "water" ideogram in Egyptian writing. The Egyptian sign had the acrophonic value /n/, from the Egyptian word for "water", nt; the adoption as the Semitic letter for /m/ was presumably also on acrophonic grounds, from the Semitic word for "water", *mā(y)-. [2] Use in writing systems Some symbols related to M were used by the Uralic Phonetic Alphabet prior to its formal standardization in 1902: [8]

Gordon, Arthur E. (1983). Illustrated Introduction to Latin Epigraphy. University of California Press. pp. 45. ISBN 9780520038981 . Retrieved 3 October 2015. roman numerals. a b c d e "What does M stand for?". The Free Dictionary. Archived from the original on 25 November 2020 . Retrieved 9 February 2021.Everson, Michael; etal. (2002-03-20). "L2/02-141: Uralic Phonetic Alphabet characters for the UCS" (PDF). Archived (PDF) from the original on 2018-02-19 . Retrieved 2018-03-24.

Figure Two: "Representative selection of proto-Sinaitic characters with comparison to Egyptian hieroglyphs", (p. 38)Ruppel, Klaas; Aalto, Tero; Everson, Michael (2009-01-27). "L2/09-028: Proposal to encode additional characters for the Uralic Phonetic Alphabet" (PDF). Archived (PDF) from the original on 2017-10-11 . Retrieved 2018-03-24.