#piston_rod  connecting rod that moves or is moved by a piston
  supertype:  connecting_rod  a rod that transmits motion (especially one that connects a rotating wheel to a reciprocating shaft)
  part of:  piston__plunger  mechanical device that has a plunging or thrusting motion
     part of:  reciprocating_engine__reciprocatingengine  an internal-combustion engine in which the crankshaft is turned by pistons moving up and down in cylinders

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