Sha (Cyrillic)


Sha is a letter of the Glagolitic and Cyrillic script. It commonly represents the voiceless postalveolar fricative, like the pronunciation of sh in sheep or the somewhat similar voiceless retroflex fricative in Russian. More precisely, the sound in Russian denoted by ш is commonly transcribed as a palatoalveolar fricative but is actually a voiceless retroflex fricative. It is used in every variation of the Cyrillic alphabet for Slavic and non-Slavic languages.
In English, Sha is romanized as sh or as š, the latter being the equivalent letter in the Latin alphabets of Czech, Slovak, Slovene, Serbian, Macedonian, Croatian, Latvian and Lithuanian.

History

Sha has its earliest origins in Phoenician Shin and is linked closely to Shin's Greek equivalent: Sigma.. Sha already possessed its current form in Saints Cyril and Methodius's Glagolitic alphabet. Most Cyrillic letter-forms were derived from the Greek, but as there was no Greek sign for the Sha sound, Glagolitic Sha was adopted unchanged. There is a possibility that Sha was taken from the Coptic alphabet, which is the same as the Greek alphabet but with a few letters added at the end, including one called "shai" which somewhat resembles both sha and shcha in appearance.

Use in mathematics

Ш has the distinction of being the most common Cyrillic letter internationally used in mathematics :
In algebraic geometry, the Tate–Shafarevich group of an Abelian variety A over a field K is denoted Ш, a notation first suggested by J. W. S. Cassels.
In a different mathematical context, some authors allude to the shape of the letter Sha when they use the term Shah function for what is otherwise called a Dirac comb.
The shuffle product is often denoted by ш.

Related letters and other similar characters