Xi (letter)

Xi (/zaɪ/ ZY or /(k)saɪ/ (K)SY;[1][2] uppercase Ξ, lowercase ξ; Greek: ξι) is the fourteenth letter of the Greek alphabet, representing the voiceless consonant cluster [ks].

In some archaic local variants of the Greek alphabet, this letter was missing.

Because this variant of the Greek alphabet was used in Magna Graecia (the Greek colonies in Sicily and the southern part of the Italian peninsula), the Latin alphabet borrowed Χ rather than Ξ as the Latin letter that represented the /ks/ cluster that was also present in Latin.

The uppercase letter Ξ is used as a symbol in various contexts.

The lowercase letter ξ is used as a symbol for: Uppercase Ξ is used as an 'E' to stylise company names/logos like Razer (styled as RΛZΞR), Tesla (styled as TΞSLA), the presidential campaigns of Joe Biden (styled as BIDΞN), musician Banners (styled as BANNΞRS), and in South Korean boy group ZE:A's newest logo (styled as "ZΞA") (Compare: Heavy Metal umlaut; Faux Cyrillic) Unicode Code Charts: Greek and Coptic (Range: 0370-03FF)