#vault  an arched brick or stone ceiling or roof
  supertype:  roof  a protective covering that covers or forms the top of a building
  part:  fenestella
  subtype:  barrel_vault  the simplest form of vault; a single continuous arch
  subtype:  groined_vault__groinedvault  two barrel vaults intersecting at right angles
  subtype:  ribbed_vault  vault that resembles a groined vault but has ribbed arches

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