The term "most wall-to-wall" is used to describe something that is completely covered or filled with no empty or blank spaces. Its antonym, on the other hand, would be "sparse" or "scattered." Sparse refers to something that is thinly spread out, while scattered means something that is dispersed irregularly. These antonyms are often used to describe a lack of density or concentration in a specific area. For example, a sparse forest would have trees that are spread apart and not densely packed, and a scattered group of rocks would be dispersed randomly across a field.