Final answer:
MarkerSize, or markersize, is a property used in graphical programming to specify the size of data point markers in a plot, measured in points.
Step-by-step explanation:
The term MarkerSize (or markersize) refers to a property that specifies the size of a marker in points when plotting data in graphical software or programming libraries such as MATLAB or Matplotlib in Python. It is used to control how large the markers that represent data points appear on a plot. MarkerSize does not affect the color, style, or line width of a marker, which are controlled by other properties such as 'markerfacecolor', 'marker', and 'linewidth' respectively.