Wiktionary
n. A particular material made of wood pulp.
Wikipedia
Beaverboard (also beaver board) is a fiberboard building material, formed of wood fibre compressed into sheets. It was originally a trademark. It has occasionally been used as a canvas by artists; most famously, the iconic painting American Gothic (1930) by Grant Wood is painted on a beaverboard panel.
Usage examples of "beaverboard".
He always did it, in these spells, and the word was like a skewer pinning her to the beaverboard among the other butterflies of his collection.
Inside, one corner had been partitioned off with beaverboard and was obviously a toilet.
Bonestell made a model of it on his dining room table, using beaverboard, plasticine, tissue paper, paint, anything at hand.
Riker parked the car at a nearby highway motel that looked as if it were made of beaverboard and staples.
In front of me, in the rear of the store, was the screen, what looked like a white-painted sheet of beaverboard, and when over my shoulder I saw the battered sixteen millimeter projector I began to think that even a dime was no bargain.
Before I could figure out what he was talking about he went to the back and from behind the beaverboard screen rolled out a big radio-phonograph and another Jumbo bottle.
The boys have built a partition of beaverboard and set up their cots in this improvised room.
But you push a lot of red-hot material up into a street like this and nearby structures made mostly of beaverboard and plywood are very quickly going to reach their flash point.