D defs.my
Entry 1 sense Webster, 1913

Substruction

· Sub·struc·tion · IPA
01 n. Underbuilding; the foundation, or any preliminary structure intended to raise the lower floor or basement of a building above the natural l…
  1. 1.
    Underbuilding; the foundation, or any preliminary structure intended to raise the lower floor or basement of a building above the natural level of the ground.(Arch.)
    “It is a magnificent strong building, with a substruction very remarkable.” Evelyn.