De-marks means to remove or erase marks or boundaries. Its antonyms would be words that suggest creating or adding boundaries and markers. Some antonyms for de-marks are "mark," "define," "limit," "establish," "distinguish," "separate," "differentiate," "discriminate," and "specify." Using these antonyms in context, we can say that we are adding markers to the territory to limit its area, distinguish its boundaries, and specify the land use. These antonyms enable us to describe the opposite action of removing markings, emphasizing putting markers or boundaries in place, marking an area in a precise way, and establishing limits.