To be restored to all that was lost.
Under ancient English common law, when a party enforced a court judgement and then that judgement was overturned on appeal, the appellant could ask the appeal court for "restitution", or financial compensation placing that appellant in the same position as if the original legal decision had not been enforced.
A new strain of common law has also developed a distinct doctrine of restitution, closely associated with unjust enrichment, where a person deprived of something of value belonging to them, can ask a court to order "restitution".
The best example is asking a court to reverse or correct a payment made in error.
See also restitutioin integrum.