scaleboard

noun2

1. •
   (no longer used) A thin slip of wood used to justify a page.

   • During the time it is working down , the head and winter will require an additional scaleboard now and then , which will be ascertained by observing whether the pull produces an adequate impression — 1808
2. •
   (no longer used) A thin veneer or leaf of wood used for covering the surface of articles of furniture etc.