Spread, Dispersion, Variability

A variable's spread is the degree to which scores on the variable differ from each other. If every score on the variable were about equal, the variable would have very little spread. There are many measures of spread. The distributions shown below have the same mean but differ in spread: The distribution on the bottom is more spread out. Variability and dispersion are synonyms for spread.

two distsributions differeing in spread