Stylistics is defined as the study of the style of different writers and types of literature and elements of language.
The study of what makes Shakespeare different from Chaucer is an example of stylistics.
the study of style as a means of analyzing works of literature and their effect; now often, specif., such study using mathematical and statistical methods
noun(used with a sing. verb)
The study of the use of elements of language style, such as metaphor, in particular contexts.