Xi (letter) Xi (letter) Xi (uppercase Ξ, lowercase ξ; ) is the 14th letter of the Greek alphabet. It is pronounced in Modern Greek, and generally or in English. In the system of Greek numerals, it has a value of 60. Xi was derived from the Phoenician letter samekh . Xi is not to be confused with the letter chi, which gave its form to the Latin letter X. Both in classical Ancient Greek and in Modern Greek, the letter Ξ represents the sound . In some archaic local variants of the Greek alphabet, this letter was missing. Instead, especially in the
History of the Greek alphabet Midas. This link may have facilitated the Greeks "borrowing" their alphabet from the Phrygians because the Phrygian letter shapes are closest to the inscriptions from Aeolis. Some scholars argue for earlier dates: Naveh (1973) for the 11th century BC, Stieglitz (1981) for the 14th century, Bernal (1990) for the 18th–13th century, some for the 9th, but none of these are widely accepted. According to legends recounted by Herodotus, the alphabet was first introduced to Greece by a Phoenician named Cadmus: Herodotus estimates that Cadmus lived sixteen hundred years earlier, or around 2000 BC. He had seen and described the Cadmean