Source : Webster's Revised Unabridged Dictionary (1913)

--Totten.

   {To cross the line}, to cross the equator, as a vessel at
      sea.

   {To give a person line}, to allow him more or less liberty
      until it is convenient to stop or check him, like a hooked
      fish that swims away with the line.

   {Water line} (Shipbuilding), the outline of a horizontal
      section of a vessel, as when floating in the water.