Crossword Genius

Chum with misstep involved in a sort of cover-up (10)

Ross

I believe the answer is:

palimpsest

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(Other definitions for palimpsest that I've seen before include "Simple taps (anag.); a manuscript" , "recycled document" , "Reused parchment" , "Recycled manuscript" .)

I've seen this clue in The Times.
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