a very thin piece of board, used for backing a picture, as a veneer, etc
scaleboard in American English
(ˈskeilˌbɔrd, -ˌbourd, ˈskæbərd)
noun
1.
a very thin board, as for the back of a picture
2. Printing
a thin strip of wood used in justifying
3.
a thin sheet of wood used as veneer
Word origin
[1705–15; scale1 + board]This word is first recorded in the period 1705–15. Other words that entered Englishat around the same time include: Romanesque, costume, inertia, unconscious, zigzag