Complement[e_all, e_1, e_2, ...] gives the elements in e_all which are not in any of the e_i.

DataDistribution[ddist, ...] represents a probability distribution of type ddist, estimated from a set of data.

Degree gives the number of radians in one degree. It has a numerical value of \[Pi]/180.

Deinitialization is an option for Dynamic, DynamicModule, Manipulate, and related constructs that specifies an expression to be evaluated when the construct can no longer be ...

Diagonal[m] gives the list of elements on the leading diagonal of the matrix m.Diagonal[m, k] gives the elements on the k\[Null]^th diagonal of m.

Dimensions[expr] gives a list of the dimensions of expr. Dimensions[expr, n] gives a list of the dimensions of expr down to level n.

DirectedGraph[g] gives a directed graph from the undirected graph g.DirectedGraph[g, conv] gives a directed graph using the conversion conv.

DisplayForm[expr] prints with low-level boxes inside expr shown in explicit two-dimensional or other form.

EdgeRenderingFunction is an option for GraphPlot and related functions that gives a function to generate the graphics primitives to use in rendering each edge.

EvaluationObject[n, expr, ...] represents an expression submitted for evaluation on any available parallel kernel.