Beam \Beam\ (b[=e]m), n. [AS. be['a]m beam, post, tree, ray of
   light; akin to OFries. b[=a]m tree, OS. b[=o]m, D. boom, OHG.
   boum, poum, G. baum, Icel. ba[eth]mr, Goth. bagms and Gr.
   fy^ma a growth, fy^nai to become, to be. Cf. L. radius staff,
   rod, spoke of a wheel, beam or ray, and G. strahl arrow,
   spoke of a wheel, ray or beam, flash of lightning. [root]97.
   See Be; cf. Boom a spar.]
   1. Any large piece of timber or iron long in proportion to
      its thickness, and prepared for use.
      [1913 Webster]

   2. One of the principal horizontal timbers of a building or
      ship.
      [1913 Webster]

            The beams of a vessel are strong pieces of timber
            stretching across from side to side to support the
            decks.                                --Totten.
      [1913 Webster]

   3. The width of a vessel; as, one vessel is said to have more
      beam than another.
      [1913 Webster]

   4. The bar of a balance, from the ends of which the scales
      are suspended.
      [1913 Webster]

            The doubtful beam long nods from side to side.
                                                  --Pope.
      [1913 Webster]

   5. The principal stem or horn of a stag or other deer, which
      bears the antlers, or branches.
      [1913 Webster]

   6. The pole of a carriage. [Poetic] --Dryden.
      [1913 Webster]

   7. A cylinder of wood, making part of a loom, on which
      weavers wind the warp before weaving; also, the cylinder
      on which the cloth is rolled, as it is woven; one being
      called the fore beam, the other the back beam.
      [1913 Webster]

   8. The straight part or shank of an anchor.
      [1913 Webster]

   9. The main part of a plow, to which the handles and colter
      are secured, and to the end of which are attached the oxen
      or horses that draw it.
      [1913 Webster]

   10. (Steam Engine) A heavy iron lever having an oscillating
       motion on a central axis, one end of which is connected
       with the piston rod from which it receives motion, and
       the other with the crank of the wheel shaft; -- called
       also working beam or walking beam.
       [1913 Webster]

   11. A ray or collection of parallel rays emitted from the sun
       or other luminous body; as, a beam of light, or of heat.
       [1913 Webster]

             How far that little candle throws his beams!
                                                  --Shak.
       [1913 Webster]

   12. (Fig.): A ray; a gleam; as, a beam of comfort.
       [1913 Webster]

             Mercy with her genial beam.          --Keble.
       [1913 Webster]

   13. One of the long feathers in the wing of a hawk; -- called
       also beam feather.
       [1913 Webster]

   Abaft the beam (Naut.), in an arc of the horizon between a
      line that crosses the ship at right angles, or in the
      direction of her beams, and that point of the compass
      toward which her stern is directed.

   Beam center (Mach.), the fulcrum or pin on which the
      working beam of an engine vibrates.

   Beam compass, an instrument consisting of a rod or beam,
      having sliding sockets that carry steel or pencil points;
      -- used for drawing or describing large circles.

   Beam engine, a steam engine having a working beam to
      transmit power, in distinction from one which has its
      piston rod attached directly to the crank of the wheel
      shaft.

   Before the beam (Naut.), in an arc of the horizon included
      between a line that crosses the ship at right angles and
      that point of the compass toward which the ship steers.

   On the beam, in a line with the beams, or at right angles
      with the keel.

   On the weather beam, on the side of a ship which faces the
      wind.

   To be on her beam ends, to incline, as a vessel, so much on
      one side that her beams approach a vertical position.
      [1913 Webster]