headstone
1. [ noun ] (architecture) the central building block at the top of an arch or vault
Synonyms: key keystone
Related terms: building_block quoin arch
2. [ noun ] a stone that is used to mark a grave
Synonyms: gravestone tombstone
Related terms: stone memorial tomb
Similar spelling:   headstock
  heatstroke
  headstrong
  headstream
  headset
  Hedstrom
  headshot
  headstand
  headstall
  head_start