From Wikipedia, the free encyclopedia
The letter M is the thirteenth letter in the Latin alphabet. Its name in English is em [ɛm].
History
The letter M derives its shape from the Phoenician Mem, via the Greek Mu (Μ, μ). Semitic Mem originally pictured water, in all probability. It is speculated that Semitic people working in Egypt c. 2000 BC borrowed a hieroglyph for Water that was first used for an alveolar nasal (/n/, because of the Egyptian word for Water, "n-t". This same symbol became used for M in Semitic, because their word for water began with that sound.
| Egyptian hieroglyph "N" |
Proto-Semitic M |
Phoenician M |
Etruscan M |
Greek Mu |
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The letter M represents the bilabial nasal consonant sound, IPA [m], in Classical languages as well as the modern languages. The Oxford English Dictionary (first edition) says that 'm' is sometimes a vowel in words like spasm and in the suffix -ism. In modern terminology, this would be described as a syllabic consonant — IPA [m̩].
Codes for computing
Alternative representations for M
In Unicode the capital M is codepoint U+004D and the lowercase m is U+006D.
The ASCII code for capital M is 77 and for lowercase m is 109; or in binary 01001101 and 01101101, correspondingly.
The EBCDIC code for capital M is 212 and for lowercase m is 148.
The numeric character references in HTML and XML are "M" and "m" for upper and lower case respectively.
Abbreviations in everyday use
- In information systems, M is often used as the abbreviation for the male sex in personal data records.
- In calendars, M is often an abbreviation for Monday or for the months March or May.
- In French, and some English works by French authors, M. is an abbreviation for Monsieur.
- In clothing, M can mean "medium size". European clothing-size standard EN 13402 defines the size code M to refer to chest girths 94–102 cm for men's clothes and bust girths 90–98 cm for women's clothes. Manufacturers also use their own non-standard defining body measurements for this size code.
- In engineering, M designates an ISO metric screw thread, as in "an M8 screw".
Arts and popular culture
Comic books
Computer games
- M is the ESRB rating symbol for Mature.
- M is the abbreviation for Mario, a Nintendo character.
- The name of a glitch Pokémon, called ’M.
Transportation
- M is the name of a New York City Subway line, the M train, which runs between Metropolitan Avenue in Queens, through Manhattan, to Bay Parkway in Brooklyn
Film
Music
Books
- M is the name of an online novel about the end of time by Michael Harold.
Photography
- In photography, most SLR cameras use M to signify manual mode, where the user sets both aperture and shutter speed.
Finance
- In common references to currency, M or m denotes million or millions, such as $25M (twenty-five million dollars).
- In traditional accounting practice, M designates thousand or thousands (from the Latin mille), and MM is used for million. Hence such traditional abbreviations as CPM for cost per thousand items of a retail good, or MCF for thousand cubic feet of (e.g.) natural gas.
- In economics, M is usually used to represent imports.
- Script capital M (Unicode 0x2133 ℳ) denotes the old German currency Goldmark.
Geographical abbreviations
Grammar
Military
- M is the US military designation for "Model" in weapons, vehicles and other equipment, but not military aircraft. Started use in the early to mid 1930's. Prior usage was the word Model of with the year of adoption or standardization. The correct current usage is with the letter M and then the number assigned, e.g. M1 rifle, etc.
- In war time, the letter M is often written on the forehead of casualties to alert medics that the patient has been given morphine.
- In the NATO phonetic alphabet, M is "Mike".
- The NATO M band ranges from 60 to 100 GHz.
Science, computing and industry
Astronomy
Biochemistry
Chemistry
- M is the symbol for the molarity of solutions.
- m is the symbol for the sample mass of compounds.
- m is also the symbol for the molality of the compound.
Colour
Computing
- M, when used as a binary prefix, means 220 = 1,048,576 (cf. M as a metric prefix below, and the prefix mebi: Mi).
- M is another name for the computer programming language MUMPS.
Mathematics
- m is used to denote slope in slope-intercept form. An M-set is the opposite of a set of uniqueness.
- Script capital M (Unicode 0x2133 ℳ) denotes a matrix.
- In the 1973 Handbook of Integer Sequences (a printed predecessor of the OEIS) sequences were numbered in lexicographic order prefixed by the letter M. Some older mathematical papers use these M numbers.
Measurement (SI system)
- M (mega) is an SI prefix denoting 106 = 1,000,000 (one million) (cf. M in computing above)
- m (milli) is an SI prefix meaning 1/1000.
- m is a widely used abbreviation for mile, as seen, for example, on road signs in the UK. In such instances, the metre is usually abbreviated as 'mtr' or similar to avoid confusion with miles.
Physics
Printing
- A capital M with a strikethrough (
M) is used in the printing industry to denote one thousand, as in run quantity. For example, 4M is the equivalent of 4,000.
Automotive
- M is the symbol for the high end performance BMW cars: M3, M5, M6,and the new Z4 M.
Roman uses
Theology
See also