#cardboard__compositionboard  a stiff moderately thick paper
  supertype:  paper  packing_material
  subtype:  binder's_board__binder_board  a cardboard used by bookbinders to make covers for books
  subtype:  card.cardboard  thin cardboard, usually rectangular
     subtype:  timecard  a card used with a time clock to record an employee's starting and quitting times each day
  subtype:  corrugated_board__corrugated_cardboard  cardboard with corrugations (can be glued to flat cardboard on one or both sides)
  subtype:  paperboard__posterboard  a cardboard suitable for making posters
  subtype:  pasteboard  stiff cardboard made by pasting together layers of paper
     subtype:  millboard  stout pasteboard used to bind books
  subtype:  strawboard  a coarse yellow cardboard made of straw pulp

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