The opposite of "meld with" can be described in a number of ways, depending on the context in which the term is being used. In some cases, the antonyms of "meld with" could include "detach," "separate," or "disconnect," meaning that two or more things are intentionally kept apart, rather than merging together. Alternatively, the antonym could be "oppose," "fight against," or "reject," indicating that one party is actively working to prevent a merger or unification. Other possible antonyms of "meld with" might include "contrast," "differentiate," or "distinguish," highlighting the differences between two objects or ideas, rather than emphasizing their similarities.