On the contrary is a phrase that is commonly used as a transition to express contradictory information. However, there are various synonyms that can be used to convey the same meaning. For instance, one could use "conversely" instead of on the contrary. This transition word means to present an argument that is opposite to what has been said earlier. Another synonym that can be used is "in contrast," which means to present the differences between two things. Additionally, you could use "contrarily" to imply opposing viewpoints or opinions. Other synonyms that can be used include "inversely," "differently," and "opposite." Therefore, it is crucial to change up the use of on the contrary now and then for variety and better understanding.