MakeExpression[boxes, form] is the low-level function used in Mathematica sessions to construct expressions from boxes.

MangoldtLambda[n] gives the von Mangoldt function \[CapitalLambda](n).

ManhattanDistance[u, v] gives the Manhattan or "city block" distance between vectors u and v.

Manipulate[expr, {u, u_min, u_max}] generates a version of expr with controls added to allow interactive manipulation of the value of u. Manipulate[expr, {u, u_min, u_max, ...

Manipulator[x] represents a manipulator with setting x in the range 0 to 1. Manipulator[Dynamic[x]] takes the setting to be the dynamically updated current value of x, with ...

MannWhitneyTest[{data_1, data_2}] tests whether the medians of data_1 and data_2 are equal.MannWhitneyTest[dspec, \[Mu]_0] tests the median difference against ...

MantissaExponent[x] gives a list containing the mantissa and exponent of a number x. MantissaExponent[x, b] gives the base-b mantissa and exponent of x.

Manual represents an option or other value that is to be selected manually, usually by some form of interactive manipulation.

MapAll[f, expr] or f //@ expr applies f to every subexpression in expr.

MapAt[f, expr, n] applies f to the element at position n in expr. If n is negative, the position is counted from the end. MapAt[f, expr, {i, j, ...}] applies f to the part of ...