Last updated
X x
(See below)
X cursiva.gif
Writing system Latin script
Type Alphabetic and Logographic
Language of origin Latin language
Greek language
Phonetic usage[ x ]
[ χ ]
[ ħ ]
[ ]
[ s ]
[ ʃ ]
[ ɕ ]
[ ]
[ ɗ ]
[ ʔ ]
[ ǁ ]
[ ʃ ]
[ d͡z ]
[ d͡ʒ ]
[ ]
[ z ]
Unicode valueU+0058, U+0078
Alphabetical position24
(speculated origin)
Time period~-700 to present
Descendants  ×
Sisters Х

Variations(See below)
Other letters commonly used with x(x)

X (named ex /ɛks/ , plural exes [1] ) is the 24th and antepenultimate letter in the modern English alphabet and the ISO basic Latin alphabet.

Letter (alphabet) grapheme in an alphabetic system of writing

A letter is a grapheme in an alphabetic system of writing. It is a visual representation of the smallest unit of spoken sound. Letters broadly correspond to phonemes in the spoken form of the language, although there is rarely a consistent, exact correspondence between letters and phonemes.

English alphabet Latin alphabet consisting of 26 letters, each having an uppercase and a lowercase form

The modern English alphabet is a Latin alphabet consisting of 26 letters, each having an upper- and lower-case form. The same letters constitute the ISO basic Latin alphabet. The alphabet's current form originated in about the 7th century from the Latin script. Since then, various letters have been added, or removed, to give the current Modern English alphabet of 26 letters:

The ISO basic Latin alphabet is a Latin-script alphabet and consists of two sets of 26 letters, codified in various national and international standards and used widely in international communication. They are the same letters that comprise the English alphabet.



Greek Chi Etruscan
Chi uc lc.svg EtruscanX-01.svg

In Ancient Greek, 'Χ' and 'Ψ' were among several variants of the same letter, used originally for /kʰ/ and later, in western areas such as Arcadia, as a simplification of the digraph 'ΧΣ' for /ks/. In the end, more conservative eastern forms became the standard of Classical Greek, and thus 'Χ' (Chi) stood for /kʰ/ (later /x/; palatalized to [ç] in Modern Greek before front vowels). However, the Etruscans had taken over 'Χ' from western Greek, and it therefore stands for /ks/ in Etruscan and Latin.

Ancient Greek Version of the Greek language used from roughly the 9th century BCE to the 6th century CE

The Ancient Greek language includes the forms of Greek used in Ancient Greece and the ancient world from around the 9th century BCE to the 6th century CE. It is often roughly divided into the Archaic period, Classical period, and Hellenistic period. It is antedated in the second millennium BCE by Mycenaean Greek and succeeded by medieval Greek.

Arcadia Regional unit in Peloponnese, Greece

Arcadia is one of the regional units of Greece. It is part of the administrative region of Peloponnese. It is situated in the central and eastern part of the Peloponnese peninsula. It takes its name from the mythological figure Arcas. In Greek mythology, it was the home of the god Pan. In European Renaissance arts, Arcadia was celebrated as an unspoiled, harmonious wilderness.

Digraph (orthography) pair of characters used to write one phoneme

A digraph or digram is a pair of characters used in the orthography of a language to write either a single phoneme, or a sequence of phonemes that does not correspond to the normal values of the two characters combined.

The letter 'Χ' ~ 'Ψ' for /kʰ/ was a Greek addition to the alphabet, placed after the Semitic letters along with phi 'Φ' for /pʰ/.

Use in writing systems


In English orthography, x is typically pronounced as the voiceless consonant cluster /ks/ when it follows the stressed vowel (e.g. ox), and the voiced consonant /ɡz/ when it precedes the stressed vowel (e.g. exam). It is also pronounced /ɡz/ when it precedes a silent h and a stressed vowel (e.g. exhaust). [2] Before i or u, it can be pronounced /kʃ/ or /ɡʒ/ (e.g. sexual and luxury); these result from earlier /ksj/ and /ɡzj/ . It also makes the sound /kʃ/ in words ending in -xion (typically used only in British-based spellings of the language; American spellings tend to use -ction). When x ends a word, it is always /ks/ (e.g. fax), except in loan words such as faux (see French, below).

English orthography is the system of writing conventions used to represent spoken English in written form that allows readers to connect spelling to sound to meaning.

In linguistics, a consonant cluster, consonant sequence or consonant compound is a group of consonants which have no intervening vowel. In English, for example, the groups and are consonant clusters in the word splits.

There are very few English words that start with x (the fewest number of any letter). When x does start a word, it is usually pronounced /z/ (e.g. xylophone, xenophobia, and xanthan); in rare recent loanwords or foreign proper names, it can also be pronounced /s/ (e.g. the obsolete Vietnamese monetary unit xu ) or /ʃ/ (e.g. Chinese names starting with Xi like Xiaomi or Xinjiang). Many of the words that start with x are of Greek origin, or standardized trademarks ( Xerox ) or acronyms (XC). In abbreviations, it can represent "trans-" (e.g. XMIT for transmit, XFER for transfer), "cross-" (e.g. X-ing for crossing, XREF for cross-reference), "Christ-" as shorthand for the labarum (e.g. Xmas for Christmas, Xian for Christian), the "crys-" in crystal (XTAL), or various words starting with "ex-" (e.g. XL for extra large, XOR for exclusive-or).

Xiaomi Chinese electronics company

Xiaomi Corporation is a Chinese electronics company headquartered in Beijing. Xiaomi makes and invests in smartphones, mobile apps, laptops, and related consumer electronics.

Xinjiang Autonomous region

Xinjiang, officially the Xinjiang Uygur Autonomous Region (XUAR), is a provincial-level autonomous region of China in the northwest of the country. It is the largest Chinese administrative division and the eighth largest country subdivision in the world, spanning over 1.6 million km2. Xinjiang contains the disputed territory of Aksai Chin, which is administered by China and claimed by India. Xinjiang borders the countries of Mongolia, Russia, Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan (Gilgit-Baltistan), and India. The rugged Karakoram, Kunlun, and Tian Shan mountain ranges occupy much of Xinjiang's borders, as well as its western and southern regions. Xinjiang also borders Tibet Autonomous Region and the provinces of Gansu and Qinghai. The most well-known route of the historical Silk Road ran through the territory from the east to its northwestern border. In recent decades, abundant oil and mineral reserves have been found in Xinjiang, and it is currently China's largest natural gas-producing region.

Greek language language spoken in Greece, Cyprus and Southern Albania

Greek is an independent branch of the Indo-European family of languages, native to Greece, Cyprus and other parts of the Eastern Mediterranean and the Black Sea. It has the longest documented history of any living Indo-European language, spanning more than 3000 years of written records. Its writing system has been the Greek alphabet for the major part of its history; other systems, such as Linear B and the Cypriot syllabary, were used previously. The alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic, and many other writing systems.

X is the third least frequently used letter in English (after q and z), with a frequency of about 0.15% in words. [3]

Letter frequency

The frequency of letters in text has been studied for use in cryptanalysis, and frequency analysis in particular, dating back to the Iraqi mathematician Al-Kindi, who formally developed the method.

Other languages

In Latin, x stood for [ks]. In some languages, as a result of assorted phonetic changes, handwriting adaptations or simply spelling convention, x has other pronunciations:

Additionally, in languages for which the Latin alphabet has been adapted only recently, x has been used for various sounds, in some cases inspired by European usage, but in others, for consonants uncommon in Europe. For these no Latin letter stands out as an obvious choice, and since most of the various European pronunciations of x can be written by other means, the letter becomes available for more unusual sounds.

Other systems

In the International Phonetic Alphabet, x represents a voiceless velar fricative.

Other uses

In mathematics, x is commonly used as the name for an independent variable or unknown value. The modern tradition of using x to represent an unknown was introduced by René Descartes in La Géométrie (1637). [5] As a result of its use in algebra, X is often used to represent unknowns in other circumstances (e.g. X-rays, Generation X, The X-Files , and The Man from Planet X ; see also Malcolm X).

In the Cartesian coordinate system, x is used to refer to the horizontal axis.

It may also be used as a typographic approximation for the multiplication sign. In mathematical typesetting, x meaning an algebraic variable is normally in italic type (), partly to avoid confusion with the multiplication symbol. In fonts containing both x (the letter) and × (the multiplication sign), the two glyphs are dissimilar.

It can be used as an abbreviation for 'between' in the context of historical dating; e.g., '1483 x 1485'.

Maps and other images sometimes use an X to label a specific location, leading to the expression "X marks the spot". [6]

The Roman numeral Ⅹ represents the number 10. [7] [8]

In art or fashion, the use of X indicates a collaboration by two or more artists, e.g. Aaron Koblin x Takashi Kawashima. This application, which originated in Japan, now extends to other kinds of collaboration outside the art world. [9] This usage mimics the use of a similar mark in denoting botanical hybrids, for which scientifically the multiplication sign (×) is used, but informally a lowercase "x" is also used.

Ancestors and siblings in other alphabets

Computing codes

Unicode 88U+0058120U+0078
UTF-8 885812078
Numeric character reference XXxx
EBCDIC family231E7167A7
ASCII 1885812078
1Also for encodings based on ASCII, including the DOS, Windows, ISO-8859 and Macintosh families of encodings.

In the C programming language, 'x' preceded by zero (0x or 0X) is used to denote hexadecimal literal values.

Other representations

NATO phonetic Morse code
X-ray –··–
ICS X-ray.svg Semaphore X-ray.svg Sign language X.svg Braille X.svg
Signal flag Flag semaphore American manual alphabet (ASL fingerspelling) Braille

See also

Related Research Articles

H letter of the Latin alphabet

H is the eighth letter in the ISO basic Latin alphabet.

The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic notation based primarily on the Latin alphabet. It was devised by the International Phonetic Association in the late 19th century as a standardized representation of the sounds of spoken language. The IPA is used by lexicographers, foreign language students and teachers, linguists, speech-language pathologists, singers, actors, constructed language creators and translators.

T letter of the Latin alphabet

T is the 20th letter in the modern English alphabet and the ISO basic Latin alphabet. It is derived from the Semitic letter taw via the Greek letter tau. In English, it is most commonly used to represent the voiceless alveolar plosive, a sound it also denotes in the International Phonetic Alphabet. It is the most commonly used consonant and the second most common letter in English-language texts.

Y letter of the Latin alphabet

Y is the 25th and penultimate letter in the modern English alphabet and the ISO basic Latin alphabet. In the English writing system, it sometimes represents a vowel and sometimes a consonant.

Z Last letter of the Latin alphabet

Z is the 26th and final letter of the modern English alphabet and the ISO basic Latin alphabet.

Chi is the 22nd letter of the Greek alphabet, pronounced or in English.

Finnish orthography is based on the Latin script, and uses an alphabet derived from the Swedish alphabet, officially comprising 29 letters but also has 2 additional letters in some loanwords. The Finnish orthography strives to represent all morphemes phonologically and, roughly speaking, the sound value of each letter tends to correspond with its value in the International Phonetic Alphabet (IPA) – although some discrepancies do exist.

A caron, háček or haček also known as a hachek, wedge, check, inverted circumflex, inverted hat, is a diacritic commonly placed over certain letters in the orthography of some Baltic, Slavic, Finnic, Samic, Berber, and other languages to indicate a change in the related letter's pronunciation.

In linguistics, a phonemic orthography is an orthography in which the graphemes correspond to the phonemes of the language. Languages rarely have perfectly phonemic orthographies; a high degree of grapheme-phoneme correspondence can be expected in orthographies based on alphabetic writing systems, but they differ in how complete this correspondence is. English orthography, for example, is alphabetic but highly nonphonemic; it was once mostly phonemic during the Middle English stage, when the modern spellings originated, but spoken English changed rapidly while the orthography was much more stable, resulting in the modern nonphonemic situation. However, because of their relatively recent modernizations when compared to English, the Italian, Turkish, Spanish, Finnish, Czech, Latvian and Polish orthographic systems come much closer to being consistent phonemic representations.

When used as a diacritic mark, the term dot is usually reserved for the Interpunct, or to the glyphs 'combining dot above' ( ◌̇ ) and 'combining dot below' ( ◌̣ ) which may be combined with some letters of the extended Latin alphabets in use in Central European languages and Vietnamese.

Italian orthography uses a variant of the Latin alphabet consisting of 21 letters to write the Italian language.

Dutch orthography uses the Latin alphabet and has evolved to suit the needs of the Dutch language. The spelling system is issued by government decree and is compulsory for all government documentation and educational establishments.

Ch (digraph) latin-script digraph

Ch is a digraph in the Latin script. It is treated as a letter of its own in Chamorro, Old Spanish, Czech, Slovak, Igbo, Kazakh, Uzbek, Quechua, Guarani, Welsh, Cornish, Breton and Belarusian Łacinka alphabets. In Vietnamese and Modern Spanish, it also used to be considered a letter for collation purposes but this is no longer common.

Portuguese orthography is based on the Latin alphabet and makes use of the acute accent, the circumflex accent, the grave accent, the tilde, and the cedilla to denote stress, vowel height, nasalization, and other sound changes. The diaeresis was abolished by the last Orthography Agreement. Accented letters and digraphs are not counted as separate characters for collation purposes.

A voiceless alveolar fricative is a type of fricative consonant pronounced with the tip or blade of the tongue against the alveolar ridge just behind the teeth. This refers to a class of sounds, not a single sound. There are at least six types with significant perceptual differences:


  1. "X", Oxford English Dictionary , 2nd edition (1989); Merriam-Webster's Third New International Dictionary of the English Language, Unabridged (1993); "ex", op. cit.
  2. Venezky, Richard (1 January 1970). The Structure of English Orthography. The Hague: Walter de Gruyter. p. 40. ISBN   978-3-11-080447-8.
  3. Mička, Pavel. "Letter frequency (English)". Algoritmy.net. Retrieved 9 February 2014.
  4. "Dizionario di ortografia e pronunzia" [Dictionary of Spelling and Pronunciation]. Dizionario di ortografia e pronunzia (in Italian). Retrieved 9 February 2014.
  5. Cajori, Florian (1928). A History of Mathematical Notations. Chicago: Open Court Publishing. p. 381. See History of algebra.
  6. "X marks the spot" . Retrieved 21 June 2016.
  7. Gordon, Arthur E. (1983). Illustrated Introduction to Latin Epigraphy. University of California Press. p. 44. Retrieved 3 October 2015.
  8. King, David A. (2001). The Ciphers of the Monks. p. 282. In the course of time, I, V and X became identical with three letters of the alphabet; originally, however, they bore no relation to these letters.
  9. "X: Mark of Collaboration - Issue No. 0053X - Arkitip, Inc". arkitip.com.
  10. Constable, Peter (2004-04-19). "L2/04-132 Proposal to add additional phonetic characters to the UCS" (PDF).
  11. Everson, Michael; Dicklberger, Alois; Pentzlin, Karl; Wandl-Vogt, Eveline (2011-06-02). "L2/11-202: Revised proposal to encode "Teuthonista" phonetic characters in the UCS" (PDF).
  12. Anderson, Deborah; Everson, Michael (2004-06-07). "L2/04-191: Proposal to encode six Indo-Europeanist phonetic characters in the UCS" (PDF).