Shin (letter) languages, as follows: In the Arabic alphabet, ' is at the original (21st) position in Abjadi order. A letter variant ' takes the place of Samekh at 15th position. "" represents , and is the 13th letter of the modern alphabet order and is written thus: The Arabic letter "šīn" was an acronym for "something" ( "šayʾ(un)" ) meaning the unknown in algebraic equations. In the transcription into Spanish, the Greek letter "chi" (χ) was used which was later transcribed into Latin "x". According to some sources, this is the origin of "x" used for the unknown in the equations.
History of the Greek alphabet Greek. Since the names of the letters "’āleph" and "hē" were pronounced and by the Greeks, with initial vowels due to the silent gutturals (the disambiguation "e psilon" "narrow e" came later), the acrophonic principle was retained for vowels as well as consonants by using them for the Greek vowel sounds and . Only the letter "‘ayin" for necessitated a change of name ("o", later "o micron"). Phoenician also had an "emphatic" consonant, "ṭēth", which did not exist in Greek. However, Greek had an aspiration distinction that Phoenician lacked, and used ṭēth for the aspirated . The Phoenician consonants "kaph"