#understructure__foundation__base__fundament__foot__groundwork__substructure  lowest support of a structure; "it was built on a base of solid rock"; "he stood at the foot of the tower"
  supertype:  support.supporting_structure  supporting structure that holds up or provides a foundation; "the statue stood on a marble support"
  subtype:  bed.understructure  raft_foundation
  part of:  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"

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