The term "most differential" refers to something that is highly distinct or diverse in comparison to other similar things. Therefore, some of the antonyms for this word could include "similar", "uniform", "identical", "unvarying", or "homogeneous". These words indicate a lack of variation and differentiation between items, rather than emphasizing the distinctions that exist between them. For example, if we are discussing a group of people, the antonyms of "most differential" would suggest that they are all very similar in terms of age, background, interests, or characteristics. In contrast, "most differential" would suggest that they are a highly diverse group.