#arch  (architecture) a masonry construction (usually curved) for spanning an opening and supporting the weight above it
  supertype:  physical_structure__structure__construction  a thing constructed; a complex construction or entity; "the structure consisted of a series of arches"; "she wore her hair in an amazing construction of whirls and ribbons"
  subtype:  abutment_arch  broken_arch  camber_arch  corbel_arch  flat_arch  pier_arch  pointed_arch  proscenium_arch  rampant_arch  round_arch  rowlock_arch  safety_arch  scoinson_arch  shouldered_arch  skeen_arch  skew_arch  squinch  trimmer_arch  triumphal_arch  Tudor_arch
  part:  keystone  springer  voussoir
  part of:  aqueduct  a conduit that resembles a bridge but carries water over a valley
  part of:  arcade.structure__colonnade  a structure composed of a series of arches supported by columns
  part of:  bridge__span  a structure that allows people or vehicles to cross an obstacle such as a river or canal or railway etc.
     part of:  transportation_system__transportation__transit  facility consisting of the roads and equipment necessary for the movement of passengers or goods
        part of:  infrastructure__base  the stock of basic facilities and capital equipment needed for the functioning of a country or area; "the industrial base of Japan"

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