1.
scratch paper; the unused back side of printed paper
paper that has been used on one side and is reused for notes or drafts on the blank side
裏紙 refers to paper that has been used on one side and is reused on the blank back side.
Writing
Common collocations
Workplace culture
Using 裏紙 is encouraged in many Japanese offices and schools as an eco-friendly practice to reduce paper waste.
Watch out
Be careful not to use paper containing confidential (機密) information as scratch paper.