Palimpsest

A palimpsest is a manuscript page from a scroll or book from which the text has been scraped or washed off so that it can be used again.
The term has come to be used in similar context in a variety of disciplines, notably architectural archaeology and geomorphology.
More information on the Wikipedia page and the Category list is .
The equivalent term for painting is Pentimento. A British Library page on the subject is here, and there is various other coverage.
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