Chi (letter) Chi (letter) Chi (uppercase Χ, lowercase χ; ) is the 22nd letter of the Greek alphabet, pronounced or in English. Its value in Ancient Greek was an aspirated velar stop (in the Western Greek alphabet: /ks/). In Koine Greek and later dialects it became a fricative (/) along with Θ and Φ. In Modern Greek, it has two distinct pronunciations: In front of high or front vowels ( or ) it is pronounced as a voiceless palatal fricative , as in German "ich" or like the "h" in some pronunciations of the English words "hew" and "human". In front of
Delta (letter) represents a voiced dental fricative , like the "th" in "that" or "this". It is romanized as "d" or "dh". The uppercase letter Δ can be used to denote: The lowercase letter δ (or 𝛿) can be used to denote: These characters are used only as mathematical symbols. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style. Delta (letter) Delta (uppercase Δ, lowercase δ or 𝛿; "délta", ) is the fourth letter of the Greek alphabet. In the system of Greek numerals it has a value of 4. It was