Legended[expr, lbl] indicates that a legend entry for expr should be created, with label lbl.

LengthWhile[list, crit] gives the number of continuous elements e_i starting at the beginning of list for which crit[e_i] is True.

MeanShiftFilter[image, r, d] replaces each pixel with the mean of the pixels in a range-r neighborhood and whose value is within a distance d.MeanShiftFilter[array, r, d] ...

MessageList[n] is a global object assigned to be a list of the names of messages generated during the processing of the n\[Null]^th input line.

Messages[symbol] gives all the messages assigned to a particular symbol.

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.

NearestFunction[data] represents a function whose values give the elements closest to an element that is supplied.

NotebookApply[notebook, data] writes data into a notebook at the current selection, replacing the first selection placeholder in data by the current selection, and then ...

NotebookClose[notebook] closes the notebook corresponding to the specified notebook object. NotebookClose[] closes the current evaluation notebook.

NotebookDelete[notebook] deletes the current selection in the notebook corresponding to the specified notebook object. NotebookDelete[] deletes the current selection in the ...