DelimiterFlashTime is an option for cells and notebooks that specifies how long in seconds a delimiter should flash when its matching delimiter is entered.
Direction is an option for Limit that specifies the direction in which the limit is taken.
Directive[g_1, g_2, ...] represents a single graphics directive composed of the directives g_1, g_2, ....
EigenvectorCentrality[g] gives a list of eigenvector centralities for the vertices in the graph g.EigenvectorCentrality[g, "In"] gives a list of in-centralities for a ...
Evaluator is an option for objects such as Button, Dynamic, and Cell that gives the name of the kernel to use to evaluate their contents.
ExpandAll[expr] expands out all products and integer powers in any part of expr. ExpandAll[expr, patt] avoids expanding parts of expr that do not contain terms matching the ...
FrameBox[box] is a low-level box construct which represents box with a frame drawn around it.
FunctionSpace is an option for FindSequenceFunction and related functions that specifies the space of functions to consider for representations.
Head
(Built-in Mathematica Symbol) Head[expr] gives the head of expr.
InterpolationPoints is an option to SmoothKernelDistribution and FunctionInterpolation that specifies the initial number of interpolation points to use.