#beam  long thick piece of wood or metal or concrete, etc., used in construction
  supertype:  structural_member  support that is a constituent part of any structure or building
  subtype:  box_beam__boxbeam__box_girder__boxgirder  a beam built up from boards; has a hollow rectangular cross section
  subtype:  cantilever  projecting horizontal beam fixed at one end only
  subtype:  girder  a beam made usually of steel; a main support in a structure
     subtype:  I-beam  girder having a cross section resembling the letter `I'
  subtype:  header.beam  a framing member crossing and supporting the ends of joists, studs, or rafters so as to transfer their weight to parallel joists, studs, or rafters
  subtype:  lintel__header  horizontal beam used as a finishing piece over a door or window
  subtype:  joist  beam used to support floors or roofs
     subtype:  floor_joist__floorjoist  joist that supports a floor
     subtype:  trimmer_joist__trimmerjoist__trimmer  joist that receives the end of a header in floor or roof framing in order to leave an opening for a staircase or chimney etc.
  subtype:  keel  one of the main longitudinal beams (or plates) of the hull of a vessel; can extend vertically into the water to provide lateral stability
     subtype:  bilge_keel__bilgekeel  either of two lengthwise fins attached along the outside of a ship's bilge; reduces rolling
  subtype:  keelson  a longitudinal beam connected to the keel of ship to strengthen it
  subtype:  rafter__balk__baulk  one of several parallel sloping beams that support a roof
  subtype:  rider_plate__riderplate  a horizontal beam (or plate) connected to the top of a ship's vertical keel or to the keelson
  subtype:  ridgepole__ridge__rooftree  a beam laid along the ridge of a roof; provides attachment for upper end of rafters
  subtype:  shoring__shore  a beam or timber that is propped against a structure to provide support
  subtype:  tie_beam__tiebeam  a horizontal beam used to prevent two other structural members from spreading apart or separating; "he nailed the rafters together with a tie beam"
  subtype:  timber  a beam made of wood
     subtype:  coulisse  a timber member grooved to take a sliding panel
     subtype:  sternpost  (nautical) the principal upright timber at the stern of a vessel
     subtype:  stringer  a long horizontal timber to connect uprights
     subtype:  two-by-four  a timber measuring (slightly under) 2 inches by 4 inches in cross section
  subtype:  trave__traverse__crossbeam  a horizontal beam that extends across something

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