Mean deviations can be perfectly replaced by other phrases that essentially carry the same meaning. For instance, the term "standard deviation" can be used to refer to the average amount by which each value or observation in a data set differs from the mean of the set. Another synonymous phrase for mean deviations is "average deviation" which calculates the average of all absolute differences from the mean of a set of numbers. The "root mean square deviation" is yet another term that is equivalent to mean deviations, which assesses the disparities between the predicted outcomes and the achieved results to gain insights into the performance of a particular system. These synonymous phrases offer alternative ways of describing or measuring variations within a dataset, making them valuable tools for statistical analysis and research.