Chi (letter)

Chi (uppercase Χ, lowercase χ; Greek: χῖ) is the 22nd letter of the Greek alphabet, pronounced /ˈkaɪ/ or /ˈkiː/ in English.

Its value in Ancient Greek was an aspirated velar stop /kʰ/ (in the Western Greek alphabet: /ks/).

In Koine Greek and later dialects it became a fricative ([x]/[ç]) along with Θ and Φ.

In Modern Greek, it has two distinct pronunciations: In front of high or front vowels (/e/ or /i/) it is pronounced as a voiceless palatal fricative [ç], as in German ich or like the h in some pronunciations of the English words hew and human. In front of low or back vowels (/a/, /o/ or /u/) and consonants, it is pronounced as a voiceless velar fricative ([x]), as in German ach.

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