Synonymy
From Conservapedia
In rhetoric, synonymy is the use of synonyms to describe something in different terms, frequently in sequence.
Examples
"This most excellent canopy, the air, look you, this brave o'erhanging firmament, this majestical roof fretted with golden fire, why, it appeareth nothing to me but a foul and pestilent congregation of vapours."
(William Shakespeare, Hamlet 2.2.299-301)