The word "extensivenesses" refers to the quality, state, or fact of being extensive. Antonyms for "extensivenesses" could include words such as limitation, constraint, narrowness, or compactness. The opposite of something that is extensive would be something that is limited in scope, small in size, or constricted. Therefore, antonyms for "extensivenesses" may be more precise, focused, or condensed. These words could be useful when one wants to describe something that is not extensive or expansive, such as a narrow pathway or a small workspace. By understanding the antonyms of "extensivenesses," one can more effectively communicate their ideas and descriptions.