scratchboard

[skrach-bawrd, -bohrd]
noun
  1. a cardboard coated with impermeable white clay and covered by a layer of ink that is scratched or scraped in patterns revealing the white surface below.

Origin of scratchboard

First recorded in 1925–30; scratch + board
Also called scratch·card, scraperboard.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018