What is "backdating"

Usage examples of "backdating".

He would transfer just a small percentage of the account balance into an offshore bank account in the Bahamas, backdating the transaction so it appeared in the Bank of Boston’s records to have been authorized prior to the account-holder’s death.

She had considered using one of Malcolm's chits that were in the desk, backdating it, using the chop from the safe but thought that unwise for the moment.