Chi
Greek.
wiktionary
From Latin chī, from Ancient Greek χεῖ(kheî).
From the Mandarin 氣／ 气 (qì) Wade-Giles romanization: chʻi⁴, from Middle Chinese 氣 (MC kʰɨiH), from Old Chinese 氣 (OC *kʰɯds, “ breath, vapor”). Compare modern Japanese 気(き)(ki), Korean 기 ( 氣, gi) and Vietnamese khí ( 氣).
From the pinyin romanization of MandarinChinese 尺(chǐ). Doublet of chek.
etymonline
chi (n.)
22nd letter of the Greek alphabet, representing a -kh- sound (see ch). The letter is shaped like an X, and so the Greek letter name was used figuratively to signify such a shape or arrangement (as in khiasma "two things placed crosswise;" khiastos "arranged diagonally; marked with an X;" khiazein "to mark with an 'X', to write the letter 'X'"). Some dialects used chi to represent the -ks- sound properly belonging to xi; Latin picked this up and the sound value of chi in Latin-derived alphabets is now that of English X.
