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
Greek alphabet parallel to the practice in Latin and other western languages. The Greek alphabet was the model for various others: It is also considered a possible ancestor of the Armenian alphabet, which in turn influenced the development of the Georgian alphabet. Apart from the daughter alphabets listed above, which were adapted from Greek but developed into separate writing systems, the Greek alphabet has also been adopted at various times and in various places to write other languages. For some of them, additional letters were introduced. Greek symbols are used as symbols in mathematics, physics and other sciences. Many symbols have traditional