Ksi (Ѯ, ѯ italics: ''Ѯ'' ''ѯ'') is a letter of the

Cyrillic script The Cyrillic script ( ) is a writing system used for various languages across Eurasia. It is the designated national script in various Slavic languages, Slavic, Turkic languages, Turkic, Mongolic languages, Mongolic, Uralic languages, Uralic, C ...

. It is a letter of the

early Cyrillic alphabet The Early Cyrillic alphabet, also called classical Cyrillic or paleo-Cyrillic, is an alphabetic writing system that was developed in Medieval Bulgaria in the Preslav Literary School during the late 9th century. It is used to write the Chur ...

, derived from the

Greek Greek may refer to: 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 of all kno ...

letter Xi (Ξ, ξ). It was mainly used in Greek

loanword A loanword (also a loan word, loan-word) is a word at least partly assimilated from one language (the donor language) into another language (the recipient or target language), through the process of borrowing. Borrowing is a metaphorical term t ...

s, especially words relating to the

Church Church may refer to: Religion * Church (building), a place/building for Christian religious activities and praying * Church (congregation), a local congregation of a Christian denomination * Church service, a formalized period of Christian comm ...

. Unlike other eliminated letters such as Omega and Yus, Ksi was a later borrowing from Greek and does not appear in any form in the

Glagolitic script The Glagolitic script ( , , ''glagolitsa'') is the oldest known Slavic alphabet. It is generally agreed that it was created in the 9th century for the purpose of translating liturgical texts into Old Church Slavonic by Saint Cyril, a monk fro ...

, which was used until the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of global history. It began with the fall of the Western Roman Empire and ...

. Ksi was eliminated from the

Russian alphabet The Russian alphabet (, or , more traditionally) is the script used to write the Russian language. The modern Russian alphabet consists of 33 letters: twenty consonants (, , , , , , , , , , , , , , , , , , , ), ten vowels (, , , , , , , , , ) ...

along with

psi Psi, PSI or Ψ may refer to: Alphabetic letters * Psi (Greek) (Ψ or ψ), the twenty-third letter of the Greek alphabet * Psi (Cyrillic), letter of the early Cyrillic alphabet, adopted from Greek Arts and entertainment * "Psi" as an abbreviat ...

omega Omega (, ; uppercase Ω, lowercase ω; Ancient Greek ὦ, later ὦ μέγα, Modern Greek ωμέγα) is the twenty-fourth and last letter in the Greek alphabet. In the Greek numerals, Greek numeric system/isopsephy (gematria), it has a value ...

, and yus in the

Civil Script Russian orthography has been reformed officially and unofficially by changing the Russian alphabet over the course of the history of the Russian language. Several important reforms happened in the 18th–20th centuries. Early changes Old East ...

of 1708 (

Peter the Great Peter I (, ; – ), better known as Peter the Great, was the Sovereign, Tsar and Grand Prince of all Russia, Tsar of all Russia from 1682 and the first Emperor of Russia, Emperor of all Russia from 1721 until his death in 1725. He reigned j ...

's ''Grazhdanka''), and has also been dropped from other secular languages. It was briefly restored in 1710 and ultimately deleted in 1735. While it was no longer used in typographic fonts, it continued to be used by the church, and since clergy actively participated in civil censuses, Ksi can be found in multiple handwritten civil texts all the way until the early 1800s. Therefore, in Russian but also in others Slavic languages, is transcribed КС and ГЗ.

In the

during Peter the Great's time, Ksi was also written similarly to an

izhitsa Izhitsa (Ѵ, ѵ; italics: ; OCS: ѷжица, Russian: ижица, Ukrainian: іжиця) is a letter of the early Cyrillic alphabet and several later alphabets, usually the last in the row. It originates from the Greek letter upsilon (Y, υ) ...

with a tail. Ksi constituted the number "60" in the Cyrillic numeral system.

Computing codes

Related letters and other similar characters

*X x : Latin letter X *Х х : Cyrillic letter Kha *Ξ ξ : Greek letter Xi

References

Cyrillic letters {{cyrillic-alphabet-stub