Mouseover[expr, over] represents an object that displays as over when the mouse pointer is over it, and as expr otherwise.

MousePosition[] gives the current mouse position in the notebook front end. MousePosition["coords"] gives the mouse position with respect to the specified coordinate ...

MoyalDistribution[\[Mu], \[Sigma]] represents a Moyal distribution with location parameter \[Mu] and scale parameter \[Sigma].

MultiedgeStyle is an option for GraphPlot and related functions that specifies how to draw multiple edges.

MultilaunchWarning is a global option that specifies whether a warning is given when you try to modify user preferences while running two copies of Mathematica simultaneously.

MultinomialDistribution[n, {p_1, p_2, ..., p_m}] represents a multinomial distribution with n trials and probabilities p_i.

MultinormalDistribution[\[Mu], \[CapitalSigma]] represents a multivariate normal (Gaussian) distribution with mean vector \[Mu] and covariance matrix \[CapitalSigma].

MultiplicativeOrder[k, n] gives the multiplicative order of k modulo n, defined as the smallest integer m such that k^m \[Congruent] 1 mod n. MultiplicativeOrder[k, n, {r_1, ...

MultivariateHypergeometricDistribution[n, {m_1, m_2, ..., m_k}] represents a multivariate hypergeometric distribution with n draws without replacement from a collection ...

MultivariatePoissonDistribution[\[Mu]_0, {\[Mu]_1, \[Mu]_2, \ ...}] represents a multivariate Poisson distribution with mean vector {\[Mu]_0 + \[Mu]_1, \[Mu]_0 + \[Mu]_2, ...