pay someone back in their own coin Definition

coin
noun

1. A small metal disc stamped for use as currency.
2. Coins generally.

verb coined, coining

1a. To manufacture (coins) from metal;
1b. To make (metal) into coins.
2. To invent (a new word or phrase).

Idiom: be coining it in

colloq
To be making a lot of money.

Idiom: the other side of the coin

The opposite way of looking at the issue under consideration.

Idiom: pay someone back in their own coin

To respond to their discourteous or unfair treatment with similar behaviour.

Idiom: to coin a phrase

ironic
Used to introduce an over-used expression.

Etymology: 14c: French meaning ‘wedge' or ‘die'.