Definition of copestone in US English:



  • 1A flat stone forming part of the coping of a wall.

    • ‘For small erections may be finished by their first architect; grand ones, true ones, ever leave the copestone to posterity.’
    • ‘In the cathedral of Vienna, the architect of the fifteenth-century Chapel of St. Barbara doubled the effect by fashioning two instances of the hanging copestones supported by flying ribs - one in each of its two bays.’
    1. 1.1 The highest stone in a building, wall, or structure.
      • ‘In 1870 (or 1871 depending on the source material), lightning struck the spire, dislodging a coping stone.’
      • ‘But in the absence of a CDS, this structure is like an arch without a coping stone.’
      • ‘Suddenly the coping stones of the archway came down.’
      • ‘Inspection covers for the arches have been removed on occasions and coping stones weighing half a ton or more have been pushed off.’
      • ‘The water level was about six feet below the bank coping stones, but during the deluge the water level rose so much that it completely covered the banking.’
    2. 1.2 A finishing touch or crowning achievement.
      • ‘The universe is finished the copestone is on, and the chips were carted off a million years ago.’
      • ‘Far from the first attack, it was the copestone of eight years marked, roughly annually, by attempted or successful terrorist operations.’


Mid 16th century: from cope + stone.