|Cyrillic letter Sha|
|The Cyrillic script|
Sha (Ш ш; italics: Ш ш) is a letter of the Glagolitic and Cyrillic script. It commonly represents the voiceless postalveolar fricative /ʃ/, like the pronunciation of ⟨sh⟩ in "sheep" or the somewhat similar voiceless retroflex fricative /ʂ/ 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.
Sha has its earliest origins in Phoenician Shin and is linked closely to Shin's Greek equivalent: Sigma (Σ, σ, ς). (Note the similar form of the modern Hebrew Shin (ש), which is probably the origin of this letter, deriving from the same Proto-Canaanite source). 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 (modern Greek uses simply "Σ/σ/ς" to spell the sh-sound in foreign words and names), 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 (Щ, щ) in appearance.
Use in mathematics
Ш has the distinction of being the only Cyrillic letter internationally used in mathematics:
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
|Unicode name||CYRILLIC CAPITAL LETTER SHA||CYRILLIC SMALL LETTER SHA|
|UTF-8||208 168||D0 A8||209 136||D1 88|
|Numeric character reference||Ш||Ш||ш||ш|
|KOI8-R and KOI8-U||251||FB||219||DB|
|Code page 855||246||F6||245||F5|
|Code page 866||152||98||232||E8|