cornerstone

  1. Noun.  A ceremonial stone set at the corner of a building, joining two exterior walls, and often inscribed with the starting and completion dates of construction, the name of the architect and owner, and other details.
  2. Noun.  By extension, that which is prominent, fundamental, noteworthy, or central.

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This entry was last updated on RefTopia from its source on 3/20/2012.