#round_arch__roundarch  an arch formed in a continuous curve
  supertype:  arch  (architecture) a masonry construction (usually curved) for spanning an opening and supporting the weight above it
  subtype:  bell_arch  a round arch resting on corbels
  subtype:  Moorish_arch__horseshoe_arch__horseshoearch  a round arch that widens before rounding off
  subtype:  Roman_arch__semicircular_arch  a round arch drawn from a single center
  subtype:  three-centered_arch__basket-handle_arch  a round arch whose inner curve is drawn with circles having three centers

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