pay someone back in their own coin
pay (one) back in (one's) own coin
To seek revenge on someone by treating them in the same negative manner as they treated one. If he's been giving you the cold shoulder, just pay him back in his own coin and start ignoring him for a while. See how he likes it. The party, now in the minority, has been paying the new majority back in their own coin by stifling their legislation initiatives at every opportunity.
pay someone back in their own coinOLD-FASHIONED
If someone has treated you badly or unfairly and you pay them back in their own coin, you treat them in exactly the same way that they have treated you. The European Community had even released lists of American unfair trade practices, paying us back in our own coin. Note: `Coin' is an old-fashioned word for currency.