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K, or k, is the eleventh
letter Letter, letters, or literature may refer to: Characters typeface * Letter (alphabet), a character representing one or more of the sounds used in speech; any of the symbols of an alphabet. * Letterform, the graphic form of a letter of the alphabe ...
in the
Latin alphabet The Latin alphabet or Roman alphabet is the collection of letters originally used by the ancient Romans to write the Latin language. Largely unaltered with the exception of extensions (such as diacritics), it used to write English and th ...
, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''kay'' (pronounced ), plural ''kays''. The letter K usually represents the
voiceless velar plosive The voiceless velar plosive or stop is a type of consonantal sound used in almost all spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is k. The sound is a ver ...
.


History

The letter K comes from the
Greek letter The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as ...
Κ ( kappa), which was taken from the Semitic kaph, the symbol for an open hand."K". ''The Oxford English Dictionary'', 2nd ed., 1977, online
/ref> This, in turn, was likely adapted by
Semitic tribes Semitic most commonly refers to the Semitic languages, a name used since the 1770s to refer to the language family currently present in West Asia, North and East Africa, and Malta. Semitic may also refer to: Religions * Abrahamic religions ** ...
who had lived in Egypt from the hieroglyph for "hand" representing /ḏ/ in the Egyptian word for hand, ⟨ ḏ-r-t⟩ (likely pronounced in
Old Egyptian The Egyptian language or Ancient Egyptian ( ) is a dead Afro-Asiatic language that was spoken in ancient Egypt. It is known today from a large corpus of surviving texts which were made accessible to the modern world following the deciphe ...
). The Semites evidently assigned it the sound value instead, because their word for hand started with that sound. K was brought into the Latin alphabet with the name ''ka'' /kaː/ to differentiate it from C, named ''ce'' (pronounced /keː/) and Q, named ''qu'' and pronounced /kuː/. In the earliest
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
inscriptions, the letters C, K and Q were all used to represent the sounds and (which were not differentiated in writing). Of these, Q was used before a rounded vowel (e.g. 'ego'), K before /a/ (e.g. 'calendis'), and C elsewhere. Later, the use of C and its variant G replaced most usages of K and Q. K survived only in a few fossilized forms such as ''Kalendae'', "the
calends The calends or kalends ( la, kalendae) is the first day of every month in the Roman calendar. The English word " calendar" is derived from this word. Use The Romans called the first day of every month the ''calends'', signifying the start of a ...
". After
Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...
words were taken into Latin, the Kappa was transliterated as a C. Loanwords from other alphabets with the sound were also transliterated with C. Hence, the
Romance languages The Romance languages, sometimes referred to as Latin languages or Neo-Latin languages, are the various modern languages that evolved from Vulgar Latin. They are the only extant subgroup of the Italic languages in the Indo-European language ...
generally use C, in imitating Classical Latin's practice, and have K only in later loanwords from other language groups. The
Celtic languages The Celtic languages ( usually , but sometimes ) are a group of related languages descended from Proto-Celtic. They form a branch of the Indo-European language family. The term "Celtic" was first used to describe this language group by Edwar ...
also tended to use C instead of K, and this influence carried over into
Old English Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlers in the mid-5th c ...
.


Pronunciation and use


English

English is now the only
Germanic language The Germanic languages are a branch of the Indo-European language family spoken natively by a population of about 515 million people mainly in Europe, North America, Oceania and Southern Africa. The most widely spoken Germanic language, E ...
to productively use "hard" (outside the digraph ) rather than (although
Dutch Dutch commonly refers to: * Something of, from, or related to the Netherlands * Dutch people () * Dutch language () Dutch may also refer to: Places * Dutch, West Virginia, a community in the United States * Pennsylvania Dutch Country People E ...
uses it in loan
words of Latin origin This is a list of Latin words with loanword, derivatives in English (and other modern languages). Ancient orthography did not distinguish between ''i'' and ''j'' or between ''u'' and ''v''. Many modern works distinguish u from v but not i from j. ...
, and the pronunciation of these words follows the same hard/soft distinction as in English). The letter is silent at the start of an English word when it comes before the letter , as in the words "knight," "knife," "knot," "know," and "knee". Like J, X, Q, and Z, the letter K is not used very frequently in English. It is the fifth least frequently used letter in the English language, with a frequency in words of about 0.8%.


Number

In the International System of Units (SI), the SI prefix for one thousand is kilo-, officially abbreviated as k: for example, prefixed to ''metre''/''meter'' or its abbreviation ''m'', ''kilometre'' or ''km'' signifies a thousand metres. As such, people occasionally represent numbers in a non-standard notation by replacing the last three zeros of the general numeral with K, as in 30K for 30,000.


Other languages

In most languages where it is employed, this letter represents the sound (with or without aspiration) or some similar sound.


Other systems

The
International Phonetic Alphabet The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standardized representation ...
uses for the
voiceless velar plosive The voiceless velar plosive or stop is a type of consonantal sound used in almost all spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is k. The sound is a ver ...
.


Related characters


Ancestors, descendants and siblings

* 𐤊 : Semitic letter Kaph, from which the following symbols originally derive * Κ κ/ϰ :
Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...
letter Kappa, from which K derives * К к : Cyrillic letter Ka, also derived from Kappa * K with
diacritic A diacritic (also diacritical mark, diacritical point, diacritical sign, or accent) is a glyph added to a letter or to a basic glyph. The term derives from the Ancient Greek (, "distinguishing"), from (, "to distinguish"). The word ''diacriti ...
s: Ƙ ƙ, Ꝁ ꝁ, Ḱ ḱ, Ǩ ǩ, Ḳ ḳ, Ķ ķ,
The palatal hook () is a type of hook diacritic formerly used in the International Phonetic Alphabet to represent palatalized consonants. It is a small, leftwards-facing hook joined to the bottom-right side of a letter, and is distinguished fro ...
, Ⱪ ⱪ, Ḵ ḵ ** Ꞣ and ꞣ were used in
Latvian orthography Latvian may refer to: *Something of, from, or related to Latvia **Latvians, a Baltic ethnic group, native to what is modern-day Latvia and the immediate geographical region **Latvian language Latvian ( ), also known as Lettish, is an Easter ...
before 1921 *The
Uralic Phonetic Alphabet The Uralic Phonetic Alphabet (UPA) or Finno-Ugric transcription system is a phonetic transcription or notational system used predominantly for the transcription and reconstruction of Uralic languages. It was first published in 1901 by Eemil Nes ...
uses various forms of the letter K: ** ** ** *ₖ : Subscript small k was used in the Uralic Phonetic Alphabet prior to its formal standardization in 1902 *Ʞ ʞ : Turned capital and small k were used in transcriptions of the
Dakota language Dakota (''Dakhótiyapi, Dakȟótiyapi''), also referred to as Dakhota, is a Siouan language spoken by the Dakota people of the Sioux tribes. Dakota is closely related to and mutually intelligible with the Lakota language. It is critically endan ...
in publications of the American Board of Ethnology in the late 19th century. Turned small k was also used for a
velar click A velar click, or more precisely a back-released velar click, is a click consonant found in paralinguistic use in languages across Africa, such as Wolof. The tongue is in a similar position to other click articulations, such as an alveolar clic ...
in the International Phonetic Alphabet but its use was withdrawn in 1970. *𝼐 : Small capital turned k is used as a
click letter Various letters have been used to write the click consonants of southern Africa. The precursors of the current IPA letters, , were created by Karl Richard Lepsius and used by Wilhelm Bleek and Lucy Lloyd, who added . Also influential were Daniel ...
*𝼃 : Small letter reversed k is used as a
Voice Quality Symbol Voice Quality Symbols (VoQS) are a set of phonetic symbols used to transcribe disordered speech for what in speech pathology is known as "voice quality". This phrase is usually synonymous with phonation in phonetics, but in speech pathology encom ...
(VoQS)


Ligatures and abbreviations

* ₭ : Lao kip * Ꝃ ꝃ, Ꝅ ꝅ, Ꞣ ꞣ : Various forms of K were used for medieval
scribal abbreviation Scribal abbreviations or sigla (singular: siglum) are abbreviations used by ancient and medieval scribes writing in various languages, including Latin, Greek, Old English and Old Norse. In modern manuscript editing (substantive and mechanica ...
s


Computing codes

: 1


Other representation


Other usage

* "K" replacing "C" in
satiric misspelling A satiric misspelling is an intentional misspelling of a word, phrase or name for a rhetorical purpose. This can be achieved with intentional malapropism (e.g. replacing ''erection'' for ''election''), enallage (giving a sentence the wrong form ...
. * K is the unit symbol for the
kelvin The kelvin, symbol K, is the primary unit of temperature in the International System of Units (SI), used alongside its prefixed forms and the degree Celsius. It is named after the Belfast-born and University of Glasgow-based engineer and phy ...
, used to measure thermodynamic temperature (note: degree sign is not used with kelvin scale). * K is the
chemical symbol Chemical symbols are the abbreviations used in chemistry for chemical elements, functional groups and chemical compounds. Element symbols for chemical elements normally consist of one or two letters from the Latin alphabet and are written with ...
for element
potassium Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosph ...
(from its Latin name ). *
Triangle K Triangle K is a kosher certification agency under the leadership of Rabbi Aryeh R. Ralbag. It was founded by his late father, Rabbi Yehosef Ralbag. The hechsher is a letter K enclosed in an equilateral triangle. Supervision and certification Th ...
. *
Unit prefix A unit prefix is a specifier or mnemonic that is prepended to units of measurement to indicate multiples or fractions of the units. Units of various sizes are commonly formed by the use of such prefixes. The prefixes of the metric system, such as ...
k, meaning 1000 times. * Josef K is the name of the principal character in
Franz Kafka Franz Kafka (3 July 1883 – 3 June 1924) was a German-speaking Bohemian novelist and short-story writer, widely regarded as one of the major figures of 20th-century literature. His work fuses elements of realism and the fantastic. It ...
's novel ''
The Trial ''The Trial'' (german: Der Process, link=no, previously , and ) is a novel written by Franz Kafka in 1914 and 1915 and published posthumously on 26 April 1925. One of his best known works, it tells the story of Josef K., a man arrested and p ...
''. * In chess notation, the letter K represents the King (WK for White King, BK for Black King). * In baseball scoring, the letter K is used to represent a strikeout. A forwards oriented K represents a "strikeout swinging"; a backwards oriented K () represents a "strikeout looking". * As abbreviation for OK, often used in emails and short text messages. * K is used as a slang term for
Ketamine Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a recreational drug. It is one of the safest anesthetics, as, in contrast with opiates, ether, and propofol, it suppresses ...
among recreational drug users. * In the
CMYK color model The CMYK color model (also known as process color, or four color) is a subtractive color model, based on the CMY color model, used in color printing, and is also used to describe the printing process itself. The abbreviation ''CMYK'' refers ...
, K represents black ink. * In International Morse code it is used to mean " over". * In fracture mechanics, ''K'' is used to represent the
stress intensity factor In fracture mechanics, the stress intensity factor () is used to predict the stress state ("stress intensity") near the tip of a crack or notch caused by a remote load or residual stresses. It is a theoretical construct usually applied to a h ...
. * In
physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...
, ''k'' usually stands for
Boltzmann's constant The Boltzmann constant ( or ) is the proportionality factor that relates the average relative kinetic energy of particles in a gas with the thermodynamic temperature of the gas. It occurs in the definitions of the kelvin and the gas constant ...
* K (logic). * K is used colloquially to mean kilometre (as in "a
10K run 1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. ...
"). * K is used to indicate thousands, especially when expressing amounts of money, e.g. $20K = twenty thousand dollars. * In the
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
under the old system (before 2001), a licence plate that begins with "K" for example "K123 XYZ" would correspond to a vehicle registered between August 1, 1992, and July 31, 1993. Again under the old system, a licence plate that ends with "K" for example "ABC 123K" would correspond to a vehicle that was registered between August 1, 1971, and July 31, 1972. * On Idaho license plates, an initial K in the plate number indicates it was issued in
Kootenai County Kootenai County ( ) is located in the U.S. state of Idaho. In 2020, the United States Census Bureau estimated the county's population at 171,362, making it the third-most populous county in Idaho and by far the largest in North Idaho, the coun ...
.


References


External links

* * * {{Latin alphabet, K} ISO basic Latin letters