Source : Webster's Revised Unabridged Dictionary (1913)

Tube \Tube\, v. t. [imp. & p. p. {Tubed}; p. pr. & vb. n.
   {Tubing}.]
   To furnish with a tube; as, to tube a well.

Tubing \Tub"ing\, n.
   1. The act of making tubes.

   2. A series of tubes; tubes, collectively; a length or piece
      of a tube; material for tubes; as, leather tubing.

Source : WordNet®

tubing
     n : conduit consisting of a long hollow object (usually
         cylindrical) used to hold and conduct objects or liquids
         or gases [syn: {tube}]