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.
Ancient Greek phonology short , which had a closer pronunciation: . Conversely, Sanskrit short was transcribed with Greek . The Greek alphabet developed from the older Phoenician alphabet. It may be assumed that the Greeks tended to assign to each Phoenician letter that Greek sound which most closely resembled the Phoenician sound. But, as with loanwords, the interpretation is not straightforward. The Greek alphabet was in turn the basis of other alphabets, notably the Etruscan and Coptic and later the Armenian, Gothic, and Cyrillic. Similar arguments can be derived in these cases as in the Phoenician-Greek case. For example, in Cyrillic, the letter