Xi (letter) dialects of most of the Greek mainland and Euboea, the sound [ks] was represented by Χ (which in classical Greek is chi, used for ). Because this variant of the Greek alphabet was used in Italy, the Latin alphabet borrowed Χ rather than Ξ as the Latin letter X. While having no Latin derivative, the Xi was adopted into the early Cyrillic alphabet, as the letter ksi (Ѯ, ѯ). The uppercase letter Ξ is used as symbol for: The lowercase letter ξ is used as a symbol for: These characters are used only as mathematical symbols. Stylized Greek text should
Coptic alphabet accepted to separate it, with the proposal noting that Coptic is never written using modern Greek letter-forms (unlike German, which may be written with Fraktur or Roman Antiqua letter-forms), and that the Coptic letter-forms have closer mutual legibility with the Greek-based letters incorporated into the separately encoded Cyrillic alphabet than with the forms used in modern Greek. In Old Coptic, there were a large number of Demotic Egyptian characters, including some logograms. They were soon reduced to half a dozen, for sounds not covered by the Greek alphabet. The following letters remained: In Unicode, most Coptic letters formerly shared codepoints