The antonyms for the word "clearing off" are: cluttering, filling up, blocking, obstructing, and dumping. Cluttering seems to be the ultimate opposite of clearing off as it refers to the action of creating a mess or disarray. Filling up implies the action of adding to an already crowded space, while blocking and obstructing indicate something that prevents a clear path or flow. Dumping refers to the state of simply abandoning items without any attempt to organize or tidy up. These antonyms highlight the importance of clearing off clutter and creating more open and organized spaces.