Number & MeasureGreek → English
Chi
/kaɪ/noun
The twenty-second letter of the Greek alphabet, best known in statistics from the chi-squared test.
The Greek roots
χεῖ
cheî
the letter chi
Literally: “the Greek letter kh”
Follow a root:χεῖ1 word
The story of the word
Latin had no such sound and wrote the letter as ch, which is why English says chorus and chaos with a k where the spelling suggests otherwise. Karl Pearson put χ into every statistics course with his test of 1900. Christian use got there first: the chi-rho monogram on banners and tombs is simply the first two letters of Χριστός.
- How it travelled
- Ancient Greek → Latin → English
Same family
chiasmuschiasma
In a sentence
The chi-squared value cleared the threshold, so the difference was not noise.
She drew a chi across the page to mark the crossing pattern.