bedrock

/ˈbɛdrɑk/
noun
  1. The solid rock layer beneath loose soil, sand, or gravel.
    • The builders drilled through the soil until they hit bedrock.
    • Erosion exposed the ancient bedrock in the canyon.
    • The foundation of the skyscraper rests on solid bedrock.
  2. The basic, fundamental principles or facts that support something.
    • Trust is the bedrock of any strong relationship.
    • A good education is the bedrock of a successful career.
    • The constitution is the bedrock of the nation's legal system.
What does "bedrock" mean? | whatsthatwordmean | whatsthatwordmean