Admix is a verb that describes the act of mixing or blending two or more substances together. The most common antonyms for admix are separate, divide, segregate, isolate, and purify. Where admix involves bringing things together, these words describe the opposite action of keeping things apart, either physically or chemically. For example, if you want to purify a substance, you'll need to eliminate any other elements or impurities. If you want to segregate items, you'll need to separate them based on certain criteria. Similarly, dividing something into different parts means creating a clear-cut separation, which is the opposite of admixing.