X
From Wikipedia, the free encyclopedia
Basic Latin alphabet | ||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
The letter X is the twenty-fourth letter in the Latin alphabet. Its name in English is ex (/ɛks/).
In phonetics, x is the IPA and X-SAMPA symbol for the voiceless velar fricative (IPA is used for pronunciation throughout this article).
Contents |
[edit] History
The consonant cluster /ks/ was, in Ancient Greek, written as either Chi Χ (Western Greek) or Xi Ξ (Eastern Greek). In the end, Chi was standardized as /kʰ/ (/x/ in Modern Greek), while Xi was standardized for /ks/. But the Etruscans had taken over Χ from older Western Greek; therefore, it stood for /ks/ in Etruscan and Latin.
It is unknown whether the letters Chi and Xi are Greek inventions, or whether they are ultimately of Semitic origin. Chi was placed toward the end of the Greek alphabet, after the Semitic letters, along with Phi, Psi, and Omega, suggesting that it was an innovation; further, there is no letter corresponding specifically to the sound /ks/ in Semitic. There was a Phoenician letter kheth with a probable sound /ħ/, somewhat similar to /kʰ/, but this was adopted into Greek as first the consonant /h/, and later, the long vowel Eta (Η,η), and does not seem to have been the source of Greek Chi. The Phoenician letter
Samekh (representing /s/) is usually considered the inspiration for Greek Xi, but as noted, Chi had a graphically distinct shape from Xi — although it may possibly have been another variant originally based on samekh. The original form of samekh may have been an Egyptian hieroglyph for the Djed column, but this too is uncertain, as no intervening Proto-Sinaitic form of this letter is attested.
Egyptian hieroglyph "column" | Phoenician S | Greek Xi | Greek Chi | Etruscan X | ||
---|---|---|---|---|---|---|
|
![]() |
![]() |
![]() |
![]() |
[edit] Usage
In some languages, as a result of assorted phonetic changes and handwriting adaptations, X has other pronunciations:
- Basque: as a spelling for [ʃ].
- English: X is a double consonant or, rather, a sign for the compound consonants [ks]; or sometimes when followed by an accented syllable beginning with a vowel, or when followed by silent h and an accented vowel [gz] (e.g. exhaust, exam); usually [z] at the beginnings of words (e.g. xylophone), and in some compounds keeps the [z] sound, as in (e.g. meta-xylene). It also makes the sound [kʃ] in words ending in -xion. It can also represent the sounds [gʒ] or [kʃ], for example, in the words luxury and sexual, respectively. Final x is always [ks] (e.g. ax/axe) except in loan words such as faux (see French, below).
- French: at the ends of words, silent (or [z] in liaison if the next word starts with a vowel). This usage arose as a handwriting alteration of final -us.
- In Norwegian, X is generally pronounced [ks], but since the nineteenth century there has been a tendency to spell it out as ks whenever possible; it may still be retained in names of people, though it is fairly rare, and occurs mostly in foreign words and SMS language.
- Spanish: In old Spanish, X was pronounced like [ʃ] as it is still currently in other Iberian languages. Later, the sound evolved to a hard [x] sound. In modern Spanish, the hard [x] sound is spelled with a j, though x is still retained for some names (notably México, which alternates with Méjico). Now, X represents the sound [s] (word-initially), or the consonat clusters [ks] and [gs] (e.g. oxígeno, examen). In American and seseo Spanish, the xc in excelente is pronounced as [ks] but in Spain, as an official rule, this combination is pronounced [ks-θ].
- Polish language doesn't use X. In loanwords, X is either replaced by ks like in 'ekstra' (extra), or gz like in 'egzotyczny' (exotic).
- Nguni languages: represents the Lateral alveolar click [ǁ].
- In some recently created alphabets based on the Roman alphabet, x represents [x]. This is the case in Kurdish, Azeri, Uzbek, Tatar and Lojban.
- In Hanyu Pinyin, the official transcription system for Mandarin Chinese, the letter x denotes the voiceless alveolo-palatal fricative /ɕ/.
- In the German and Italian languages, X is used mainly in foreign loan words.
No words in the Basic English vocabulary begin with X, but it occurs in words beginning with other letters. It is often found in a word with an E before it. Otherwise it is the third most rarely used letter in the English Language.
[edit] Codes for computing
NATO phonetic | Morse code | ||
X-ray | |||
![]() |
![]() |
![]() |
![]() |
Signal flag | Semaphore | ASL Manual | Braille |
In Unicode the capital X is codepoint U+0058 and the lowercase x is U+0078.
The ASCII code for capital X is 88 and for lowercase x is 120; or in binary 01011000 and 01111000, correspondingly.
The EBCDIC code for capital X is 231 and for lowercase x is 167.
The numeric character references in HTML and XML are "X" and "x" for upper and lower case respectively.
[edit] Meanings of X
- In a general sense, X represents a generic placeholder variable, whose value is unknown or secret but within a set defined by context, as in project X or mister X. This usage is borrowed from mathematics (see below) and acquired some specialized meanings, listed here.
- Malcolm X changed his surname to "X" to symbolize that his African name was lost in slavery; some other members of the Nation of Islam followed his example.
- In aeronautics, X is the designation given to an experimental aircraft of the US government, such as the X-1 rocketplane that first broke the sound barrier. It is also a prefix to experimental types of US military aircraft, such as the XB-70.
- In anime, X is a series produced by Clamp based on the Japanese manga X (see X (anime)) which has also been adapted into a 1996 feature film and a 2001 television series.
- In astronomy,
- Planet X is a hypothetical planet in the Solar System beyond the orbit of Neptune.
- X stands for a comet of unknown orbit, as in X/1106 C1, one of whose fragments is thought to have been the Great Comet of 1882.
- X stands for a December 1 through 15 discovery, in the provisional designation of a comet (e.g. C/1927 X1, Comet Skjellerup-Maristany) or asteroid (e.g. (3757) 1982 XB).
- On paper ballots with square boxes, the symbol used in America to indicate one's choice is often in the form of an X and is so called. This extends to similar boxes on other forms. However, in Japan and Korea, boxes have a circle drawn in them to indicate one's choice, while those which are rejected are marked with an X. In Europe and many Commonwealth countries, rejection is also signified with an X, while a tick indicates one's selection.
- In beverages, X is a symbol for an alcoholic proof of 50; multiple Xes indicate multiples of 50.
- In ten-pin bowling, an X is a symbol for a strike — knocking down all ten pins in a the first roll of a frame.
- In cabalistic philosophy, X references both birth and death.
- In chemistry, X is used to represent a halogen atom or ion. This is generally used to represent any halogen in a general formula demonstrating reactions or compounds common to all halogens and is used instead of the symbol for the element.
- In clothing, X is used as an abbreviation for extra, such as XXL for extra-extra-large or XS for extra-small.
- In computing: X is
- the X Window System, a free-software graphical windowing system developed at MIT and standard on Unix-like operating systems including Linux,
- Ctrl-X (in Windows) and Command-X (in MacOS), the keyboard shortcut for cutting, that is, removing the selected text, image or sound and placing it on the clipboard,
- the multiplication of the CD-ROM (and DVD) disc spin and transfer rate compared to the original speed,
- Mac OS X, the Apple Computer operating system,
- an ITU-T series of recommendations on Data networks and open system communication, including, for example, X.509; and
- the repetition operator in the Perl programming language.
- In economics, especially national income accounting, X is usually used to represent exports.
- In electrical engineering, X is the symbol for reactance.
- In English:
- X is an abbreviation for Christ, as in Xmas (Christmas), X(t)ian (Christian), and Xianity (Christianity), due to its Greek name.
- X also appears in other jargon or trade abbreviations, such as "xtal" (Crystal), "xant" (chrysanthemum), "reXn" or "rxn" (reaction), "Xlation" (translation), "SXSW" (South by Southwest festival), "RX" (receive) or (recrystallized), "TX" (transmit), "DX" (distance), and "WX" (weather).
- In American slang, X is often used as an abbreviation of ecstasy (MDMA), a synthetic drug.
- In written communication, X can be paired with the letter O to convey a warm sentiment (traditionally Hugs and Kisses) and is typically used as a closing, e.g. "XO, Bob".
- In Italian, X is used as an abbreviation for per (for) and for other uses of per, ie. xché for perché (because).
- In film:
- X is a rating given to films suitable for an adult-only audience; see X-rated. NC-17 has replaced the X rating in the United States. The United Kingdom replaced the X rating with the 18 certificate. Australia retains the X rating.
- X is the title of a 1928 German film; see X (film)
- X is also the title of a 1963 American science-fiction film; see X (1963 film).
- The X-Files was a popular 1990s American science fiction television series.
- In both JFK and The X-Files, X is a mysterious informant who supplies the main character with information regarding a government conspiracy.
- In finance, X is the U.S. ticker symbol for United States Steel Corporation.
- In French education, X is a nickname for the École Polytechnique and its alumni.
- In games, X is representation for a cross in games like tic tac toe (naughts and crosses)
- In Gridiron football playbooks, X often represents the players on the defense, and O the offense, producing the expression "X's and O's" to describe the plays as drawn up on paper, in contrast to the execution thereof.
- In genetics, X denotes the X chromosome.
- In sex, XX denotes female in the XY sex-determination system.
- In legal documents, X can stand for the signature of an illiterate signatory, as long as the document is countersigned by a literate witness. In the Middle Ages, this represented a cross and so signified a Christian signatory, whereas illiterate Jews used a circle (kikel).
- In mathematics:
- x commonly represents an unknown variable. Even though any letter can be used, x is the most common choice. This usage can be traced back to the Arabic word šay' شيء = "thing", which in translated algebra texts and similar was taken into Old Spanish with the pronunciation "šei", which was written xei, which was soon habitually abbreviated to x. (Spanish pronunciation of "x" has changed since.) But some sources say that this x is an abbreviation of Latin causa which was a translation of Arabic شيء. That started the habit of using letters to represent quantities in algebra. In mathematics a "curly x" (
) is often used to avoid potential confusion with the multiplication symbol.
- x is the usual symbol for the variable represented on the horizontal axis (ordinate) in analytic geometry.
- X means 10 in Roman numbers.
- The symbol
(×), similar to the lowercase x, denotes multiplication.
- x commonly represents an unknown variable. Even though any letter can be used, x is the most common choice. This usage can be traced back to the Arabic word šay' شيء = "thing", which in translated algebra texts and similar was taken into Old Spanish with the pronunciation "šei", which was written xei, which was soon habitually abbreviated to x. (Spanish pronunciation of "x" has changed since.) But some sources say that this x is an abbreviation of Latin causa which was a translation of Arabic شيء. That started the habit of using letters to represent quantities in algebra. In mathematics a "curly x" (
- In military science, X is the US Navy hull classification symbol for Submersible Craft.
- In optics, an x marks the magnification of a lens or instrument. A 2x lens shows an image twice bigger than reality.
- In photography, X denotes exact time in flash synchronization.
- In physics, the X-ray is a form of electromagnetic radiation.
- In popular music:
- X is a song by the pop group Liberty X.
- see X (album) for albums entitled "X"
- see X (band) for bands named "X"
- seeX (author) for authors named "X"
- As the first letter of a postal code:
- In Canada, X stands for Nunavut and the Northwest Territories.
- In publishing, X is used in ISBN and ISSN numbers as an eleventh one-digit numeral, following 9.
- In radio,
- the X band ranges from 8 to 12.5 GHz.
- X is a roller coaster at Six Flags Magic Mountain.
- In Roman numerals, X denotes ten (there are also separate Unicode characters for this number, 0x2169 "Ⅹ" and 0x2179 "ⅹ").
- In semiotics, an X over something denotes elimination, prohibition or erasure.
- In sociology, X denotes Generation X.
- In superhero comic books, an X usually denotes a connection to the popular X-Men franchise, especially when used as a prefix.
- In treasure-hunting, X is used to designate the location of treasure, i.e. X marks the spot.
- In United States politics, X is the pseudonym of the person who blew the whistle on the Watergate crisis.
- In United States public policy, X is the author (George F. Kennan) of the X article published in Foreign Affairs.
[edit] See also
Similar non-Latin letters:
- Χ : Greek letter Chi
- Х : Cyrillic Kha
- メ : Me (Japanese katakana character)
- א (Hebrew aleph) sometimes looks like X when handwritten.
- 乂 : A Japanese or Chinese character usually used in names, pronounced as "Ai".
Unicode has also several similar non-letter symbols:
- × : multiplication sign
- ╳ : box drawings left diagonal cross
- ✕ : multiplication x
- ✗ : ballot x
- ✘ : heavy ballot x
- × : vector or cross product
|