#railroad_tie__tie__crosstie__sleeper  one of the cross braces that support the rails on a railway track; "the British call a railroad tie a sleeper"
  supertype:  bracing__brace  a structural member used to stiffen a framework
  part of:  railroad_track__railroad__railway  a line of track providing a runway for wheels; "he walked along the railroad track"
     part of:  rail_line__line__railway_line__railwayline  railroad track and roadbed

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