codex

n.A document, especially an old manuscript, made from two or more flat pieces that have been hinged to open like the leaves of a modern book.

Notes

The hinged binding of a codex distinguishes it from a scroll. The leaves of a codex may be made of any material, including metal, wood, ivory, or more commonly paper, papyrus, or vellum. The term is derived from early versions of the Christian Bible.