Which term refers to a literary device that juxtaposes contrasting ideas or elements?

The term that refers to a literary device juxtaposing contrasting ideas or elements is antithesis. Antithesis involves setting opposing or contrasting ideas side-by-side in a sentence or phrase to create a relationship between them. This technique can highlight contrasts in themes, characters, or sentiments, allowing the reader to see the relationship between opposing forces more clearly. For example, in the phrase "It was the best of times, it was the worst of times," the contrasting notions enhance the complexity of the situation being described.

Other terms like oxymoron and paradox also deal with conflicting elements, but they function differently; an oxymoron combines contradictory terms into a single phrase (e.g., "deafening silence"), while a paradox presents a statement that seems self-contradictory but may reveal a deeper truth. Irony involves a disparity between expectation and reality, which does not necessarily focus on the direct juxtaposition of contrasting ideas. Thus, antithesis is the most fitting term for describing the juxtaposition of opposing ideas or elements in literature.