ShowCursorTracker is an option for Cell that specifies whether an elliptical spot should appear momentarily to guide the eye if the cursor position jumps.
SpheroidalJoiningFactor[n, m, \[Gamma]] gives the spheroidal joining factor with degree n and order m.
SpheroidalS1Prime[n, m, \[Gamma], z] gives the derivative with respect to z of the radial spheroidal function S_n^m, (1)(\[Gamma], z) of the first kind.
SpheroidalS2[n, m, \[Gamma], z] gives the radial spheroidal function S_n^m, (2)(\[Gamma], z) of the second kind.
SpheroidalS2Prime[n, m, \[Gamma], z] gives the derivative with respect to z of the radial spheroidal function S_n^m, (2)(\[Gamma], z) of the second kind.
Splice
(Built-in Mathematica Symbol) Splice["file"] splices Mathematica output into an external file. It takes text enclosed between < * and * > in the file, evaluates the text as Mathematica input, and replaces ...
SqrtBox
(Built-in Mathematica Symbol) SqrtBox[x] is a low-level box construct that represents the displayed object Sqrt[x] in notebook expressions.
StabilityMargins is an option to frequency response plots such as BodePlot, NyquistPlot, and NicholsPlot that specifies the gain and phase margins to be shown on the plot.
SubscriptBox[x, y] is the low-level box representation for x_y in notebook expressions.
SuperscriptBox[x, y] is the low-level box representation for x^y in notebook expressions.