Chi (letter)

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 some pronunciations of "h" in English words like 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 or Spanish j.

In ancient times, some local forms of the Greek alphabet used the chi instead of xi to represent the /ks/ sound.

Chi was also included in the Cyrillic script as the letter Х, with the phonetic value /x/ or /h/.

In Plato's Timaeus, it is explained that the two bands that form the soul of the world cross each other like the letter Χ. Plato's analogy, along with several other examples of chi as a symbol occur in Thomas Browne's discourse The Garden of Cyrus (1658).