A form of fiberboard made of wood pulp compressed into sheets.
1957, J. D. Salinger, "Zooey", in, 1961, Franny and Zooey, 1991 LB Books edition, page 176,
Instead, he turned around and deliberately faced a sheet of what had once been snow-white beaverboard that was nailed uncompromisingly to the back of the door.