EllipticK[m] gives the complete elliptic integral of the first kind K(m).
EllipticTheta[a, u, q] gives the theta function \[CurlyTheta]_a (u, q) (a = 1, ..., 4).
ExpGammaDistribution[\[Kappa], \[Theta], \[Mu]] represents an exp-gamma distribution with shape parameter \[Kappa], scale parameter \[Theta], and location parameter \[Mu].
FisherZDistribution[n, m] represents a Fisher z distribution with n numerator and m denominator degrees of freedom.
Minors
(Built-in Mathematica Symbol) Minors[m] gives the minors of a matrix m. Minors[m, k] gives the k\[Null]\[Null]^th minors.
MultivariateHypergeometricDistribution[n, {m_1, m_2, ..., m_k}] represents a multivariate hypergeometric distribution with n draws without replacement from a collection ...
NProduct[f, {i, i_min, i_max}] gives a numerical approximation to the product \[Product]i = i_min i_max f.NProduct[f, {i, i_min, i_max, di}] uses a step di in the product.
PolarTicks is an option for sector charts and polar plots that specifies tick marks for polar axes.
PowerDistribution[k, a] represents a power distribution with domain parameter k and shape parameter a.
RankedMax[list, n] gives the n\[Null]^th largest element in list.