The word "unlevel" denotes something that is not even or not flat. Its antonyms refer to the opposite state of levelness. These antonyms include terms like flat, even, smooth, uniform, and constant. Flat implies a surface that is plain and lacking in any significant variation, while smooth refers to something that is free of bumps or roughness. A surface that is uniform has a consistent appearance throughout. And constant implies a surface that is unchanging in its height or overall shape. These antonyms can help you describe surfaces or objects that are level or uneven, depending on the context in which they are used.