[1] : The Collaborative International Dictionary of English v.0.48

underpin \un`derpin"\, v. t. imp.  p. p. underpinned; p.
   pr.  vb. n. underpinning.
   1. to lay stones, masonry, etc., under, as the sills of a
      building, on which it is to rest.
      1913 webster

   2. to support by some solid foundation; to place something
      underneath for support.
      1913 webster
see also:
underpinned underpinning 

[2] : The Collaborative International Dictionary of English v.0.48

underpinning \un"derpin`ning\, n.
   1. the act of one who underpins; the act of supporting by
      stones, masonry, or the like.
      1913 webster

   2. arch.
      a that by which a building is underpinned; the material
          and construction used for support, introduced beneath
          a wall already constructed.
      b the foundation, esp. of a frame house. local, u. s.
          1913 webster

[3] : WordNet (r) 2.0

underpinning
     see underpin
see also:
underpin 

[4] : WordNet (r) 2.0

underpin
     v 1: support from beneath
     2: support with evidence or authority or make more certain or
        confirm; "the stories and claims were born out by the
        evidence" syn: corroborate, bear out, support
     also: underpinning, underpinned
see also:
corroborate bear out support underpinning underpinned 

[5] : Moby Thesaurus II by Grady Ward, 1.0

48 moby thesaurus words for "underpinning":
   base, basement, basis, bearing wall, bed, bedding, bedrock, brace,
   buttress, column, floor, flooring, fond, footing, foundation,
   fundament, fundamental, ground, grounds, groundwork, hardpan,
   infrastructure, pavement, principle, prop, radical, riprap,
   rock bottom, root, rudiment, seat, seating, shore, sill,
   solid ground, solid rock, stay, stereobate, stylobate, substratum,
   substruction, substructure, terra firma, underbuilding,
   undercarriage, undergirding, understruction, understructure

Underpinning >> U Words
Underpinning, definition of term: Underpinning
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