How to say "cardboard" in Japanese

• 厚紙あつがみCommon
  nounThe broad, general word: it covers cardboard and also thick paper generally, so it fits whenever you simply mean a stiff, thick sheet — for example, card used for crafts or school art projects.
  ２．ペンで厚紙あつがみにブーメランの形かたちを描えがく。描えがいたブーメランを切り取きりとる。↗

  2. Draw a boomerang shape on the card with a pen. Cut out the boomerang you've drawn.
• 板紙いたがみCommon
  nounThe specific term for paperboard: the stiff board material that boxes, cartons, and other packaging are made from. Choose it when the subject is the packaging material itself rather than just any thick sheet.

Choose 厚紙 when you simply mean thick, stiff paper or cardboard in a general sense; choose 板紙 when you mean paperboard specifically — the board material used to make boxes and cartons.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 厚紙あつがみcardboard
• 板紙いたがみcardboard
• ボール紙ボールがみcardboard
• ダンボール(corrugated) cardboard