#ratchet__rachet__ratch  mechanical device consisting of a toothed wheel or rack engaged with a pawl that permits it to move in only one direction
  supertype:  mechanical_device  mechanism consisting of a device that works on mechanical principles
  part of:  spiral_ratchet_screwdriver
  part:  pawl__detent__click__dog  a hinged catch that fits into a notch of a ratchet to move a wheel forward or prevent it from moving backward
  part:  ratchet_wheel__ratchetwheel  toothed wheel held in place by a pawl or detent and turned by a lever

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