The antonyms for the word "more dilating" could be words like constricting, narrowing, tightening, or reducing instead of expanding. These words indicate a decrease or restriction in size, volume, or extent. While dilating means to widen or enlarge, its antonyms have the opposite meaning, implying a contraction or closing. For example, when blood vessels constrict, the flow of blood decreases, causing a decrease in the size of the vessels. Similarly, when a muscle tightens, it becomes smaller and shorter. In conclusion, antonyms for the word "more dilating" refer to the opposite action of reducing or contracting.