#nut.block  a small square or hexagonal metal block with internal screw thread to be fitted onto a bolt
  supertype:  block  a solid piece of something (usually having flat rectangular sides); "the pyramids were built with large stone blocks"
  subtype:  hex_nut  locknut  square_nut  stuffing_nut  wing_nut
  part of:  nut_and_bolt__nutandbolt  a fastener made by screwing a nut onto a threaded bolt

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