copingstone
/ˈkoʊpɪŋ ˌstoʊn/
noun
- Alternative spelling of coping stone; a stone or slab placed on top of a wall, fence, or building to protect it from weather and to finish it.
- They used granite copingstones for the new retaining wall.
- The copingstone on the garden wall was loose after the storm.
- Each copingstone was carefully cut to fit the curve of the wall.