To date something with a date that is earlier than the actual date it was written or created.
From 'fore-' (before) plus 'date' from Old French 'date', from Latin 'data' (feminine past participle of 'dare' meaning 'to give'). Legal and documentary term.
Historians can catch forged documents by detecting when something has been 'foredated'—the paper quality, ink, and other physical evidence often reveal that a document wasn't actually written when the date claims!
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