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

abutment \abut"ment\ .abu^t"ment, n.
   1. state of abutting.
      1913 webster

   2. that on or against which a body abuts or presses; as
      a arch. the solid part of a pier or wall, etc., which
          receives the thrust or lateral pressure of an arch,
          vault, or strut. --gwilt.
      b mech. a fixed point or surface from which resistance
          or reaction is obtained, as the cylinder head of a
          steam engine, the fulcrum of a lever, etc.
      c in breech-loading firearms, the block behind the
          barrel which receives the pressure due to recoil.
          1913 webster

[2] : WordNet (r) 2.0

abutment
     n 1: point of contact between two objects or parts
     2: a masonry support that touches and directly receives thrust
        or pressure of an arch or bridge

Abutment >> A Words
Abutment, definition of term: Abutment
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