Pipelaying \Pipe"lay`ing\, n., or Pipe laying \Pipe" lay`ing\ 1. The laying of conducting pipes underground, as for water, gas, etc. [1913 Webster] 2. (Polit. Cant) The act or method of making combinations for personal advantage secretly or slyly; -- in this sense, usually written as one word. [U.S.] [1913 Webster] pipeline