The word re-fine means to purify, filter, or improve something. Its antonyms will be words that have opposite meanings such as coarsen, adulterate, degrade, or contaminate. Coarsen means to make something rougher or less refined. Adulterate means to mix a pure substance with something impure or to make it less valuable. Degrade means to lower its quality, rank or status. Contaminate means to pollute or taint a pure substance with something harmful or unwanted. These antonyms of re-fine are important to understand since they help us determine the opposite of refining something.