"χ" and "Χ" redirect here. For the consonant represented byχ in IPA, seeVoiceless uvular fricative."Khi" redirects here. For other uses, seeKHI.Not to be confused withX,×, orΞ.
Chi isromanized as⟨ch⟩ in most systematic transliteration conventions, but sometimes⟨kh⟩ is used.[3] In addition, in Modern Greek, it is often also romanized as⟨h⟩ or⟨x⟩ in informal practice.
In ancient times, somelocal forms of theGreek alphabet used the chi instead ofxi to represent the /ks/ sound. This was borrowed into the earlyLatin language, which led to the use of the letterX for the same sound in Latin, and many modern languages that use theLatin alphabet.
InPlato'sTimaeus, it is explained that the two bands that form thesoul of the world cross each other like the letter Χ. Plato's analogy, along with several other examples ofchi as a symbol occur inThomas Browne's discourseThe Garden of Cyrus (1658).
Chi orX is often used to abbreviate the nameChrist, as in the holidayChristmas (Xmas). When fused within a single typeface with the Greek letterrho, it is called theChi Rho and used to represent the person of Jesus Christ.
^"Greek language | Definition, Alphabet, Origin, & Facts | Britannica".www.britannica.com. 2024-12-20. Retrieved2025-02-09.Some differences in transliteration result from changes in pronunciation of the Greek language; others reflect convention, as for example the χ (chi or khi), which was transliterated by the Romans as ch (because they lacked the letter k in their usual alphabet). In Modern Greek, however, the standard transliteration for χ is kh.
^Weisstein, Eric W."Chromatic Number".mathworld.wolfram.com. Retrieved2025-02-09.The chromatic number of a graph G is most commonly denoted χ (G) (e.g., Skiena 1990, West 2000, Godsil and Royle 2001, Pemmaraju and Skiena 2003),...
^Asimov, Isaac (1963).The Human Brain. Boston: Houghton Mifflin.
^Jiles, David (2016).Introduction to magnetism and magnetic materials (Third ed.). Boca Raton London New York: CRC Press, Taylor & Francis Group. p. 42.ISBN978-1-138-44149-1.We can now make a general statement for the permeabilityμ and susceptibilityχ
