M, or m, is the thirteenth letter of the modern English alphabet and the ISO basic Latin alphabet. Its name in English is em (pronounced /ˈɛm/), plural ems. 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.