boards : Common term for the covers of a hardbound book.

jacket : Sometimes used as another term for dust jacket, a protective and often decorative wrapper, usually made of paper which wraps around the binding of a book

8vo : Short for Octavo, A book whose page size is approximately 8-10 inches tall. The size is based on a sheet of paper 25 inches by 38 inches, the size of paper traditionally used by book printers, which has been folded and cut into 16 pages.. Unfortunately often misunderstood to mean 8 volumes.

endpaper : The double leaves bound into a book at the front and rear after printing. One side is glued to the inner portion of the boards (the paste-down) and the other is left loose (free endpaper).