SaveAutoDelete is an option for ErrorBox objects that specifies whether the ErrorBox is automatically deleted when the notebook containing it is saved.
ShortDownArrow[x, y, ...] displays as x\[ShortDownArrow]y\[ShortDownArrow]....
ShortUpArrow[x, y, ...] displays as x\[ShortUpArrow]y\[ShortUpArrow]....
ShowCellTags is an option for Cell that specifies whether to display tags for a cell.
Sinc
(Built-in Mathematica Symbol) Sinc[z] gives sinc(z).
SpellingCorrection is an option for StringMatchQ, Names, and related functions that specifies whether strings should be considered to match even when a small fraction of the ...
SpheroidalPSPrime[n, m, \[Gamma], z] gives the derivative with respect to z of the angular spheroidal function PS n, m (\[Gamma], z) of the first kind.
SpheroidalQS[n, m, \[Gamma], z] gives the angular spheroidal function QS n, m (\[Gamma], z) of the second kind.
SpheroidalQSPrime[n, m, \[Gamma], z] gives the derivative with respect to z of the angular spheroidal function QS n, m (\[Gamma], z) of the second kind.
Square
(Built-in Mathematica Symbol) Square[x] displays as \[Square]x.