unring

Etymology
en

Verb

 * 1) Hypothetically, to reverse the act of ringing, or the consequences of the action.
 * In a criminal trial, if the prosecution brings in inadmissible evidence that would unfairly prejudice the accused, a mistrial may be warranted. Having the judge admonish the jury to disregard the evidence might not be enough, as the saying goes, 'You can't unring the bell.'

Verb

 * 1)  To remove a ring from.