palimpsest.

About palimpsest

In textual studies, a palimpsest is a manuscript page, either from a scroll or a book, from which the text has been scraped or washed off in preparation for reuse in the form of another document. Parchment was made of lamb, calf, or goat skin and was expensive and not readily available, so, in the interest of economy, a page was often reused by scraping off the previous writing. In colloquial usage, the term palimpsest is also used in architecture, archaeology and geomorphology to denote an object made or worked upon for one purpose and later reused for another; for example, a monumental brass on which the blank reverse side has been re-engraved.