The Collaborative International Dictionary of English v.0.48:

Helm \Helm\, n. [OE. helme, AS. helma rudder; akin to D. & G.
   helm, Icel. hj[=a]lm, and perh. to E. helve.]
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   1. (Naut.) The apparatus by which a ship is steered,
      comprising rudder, tiller, wheel, etc.; -- commonly used
      of the tiller or wheel alone.
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   2. The place or office of direction or administration. "The
      helm of the Commonwealth." --Melmoth.
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   3. One at the place of direction or control; a steersman;
      hence, a guide; a director.
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            The helms o' the State, who care for you like
            fathers.                              --Shak.
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   4. [Cf. Helve.] A helve. [Obs. or Prov. Eng.]
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   Helm amidships, when the tiller, rudder, and keel are in
      the same plane.

   Helm aport, when the tiller is borne over to the port side
      of the ship.

   Helm astarboard, when the tiller is borne to the starboard
      side.

   Helm alee, Helm aweather, when the tiller is borne over
      to the lee or to the weather side.

   Helm hard alee, Helm hard aport, Helm hard astarboard,
      etc., when the tiller is borne over to the extreme limit.


   Helm port, the round hole in a vessel's counter through
      which the rudderstock passes.

   Helm down, helm alee.

   Helm up, helm aweather.

   To ease the helm, to let the tiller come more amidships, so
      as to lessen the strain on the rudder.

   To feel the helm, to obey it.

   To right the helm, to put it amidships.

   To shift the helm, to bear the tiller over to the
      corresponding position on the opposite side of the vessel.
      --Ham. Nav. Encyc.
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