Chi (letter)

Chi (uppercase Χ, lowercase χ; Ancient Greek χῖ) is the 22nd letter of the Greek alphabet.

It is derived from the Phoenician letter samekh ().

Usage:

In Ancient and Modern Greek, the letter represents the voiceless velar fricative /x/, as in the Scottish word "loch" or the German word "Bach."

In some contexts, chi can also represent the voiced velar fricative /ɣ/, similar to the "g" in the Dutch word "gaan." This pronunciation is less common.

Pronunciation in English:

In English-speaking countries, "chi" is often pronounced as /kaɪ/ (rhyming with "sky"). This is a common pronunciation, especially when referring to fraternities, sororities, or other organizations that use the Greek alphabet.

Related Symbols and Meanings:

• In mathematics and statistics, lowercase chi (χ) is used to represent the chi distribution and the chi-squared distribution. It is also used as a variable name.

• Uppercase chi (Χ) is sometimes used as an abbreviation for Christ. This is often seen in the abbreviation "Xmas" for Christmas.

• Chi is used in various other fields, including physics, chemistry, and psychology, often representing specific variables or concepts within those disciplines.

Unicode:

• Uppercase Chi: U+03A7
• Lowercase Chi: U+03C7