Ceremonial building block, dated or otherwise inscribed, usually placed in an outer wall of a building to commemorate its dedication. Often the stone is hollowed out to contain newspapers, photographs, or other documents reflecting current customs, with a view to their historical use when the building is remodeled or demolished. Originally placed at a corner, the stone may today be placed elsewhere on the facade.
This entry comes from Encyclopædia Britannica Concise.
For the full entry on cornerstone, visit Britannica.com.
Seen & Heard
What made you look up cornerstone? Please tell us what you were reading, watching or discussing that led you here.