9 Q Without U Words for Words With Friends
A reduction, esp of wages or production (1942+)
Reverting data in a database to an earlier state, usually in response to an error or aborted operation.
In a transaction based database system, transactions are considered atomic. If an error occurs while performing a transaction, the database is automatically rolled back to the state at the previous commit.
Rollback may also be performed by an explicit rollback transaction.