coin debasement
act of decreasing the amount of precious metal in a coin, while continuing to circulate it at face value
en-GB/ˈkɔɪn dɪˈbeɪsmənt/
en-US/ˈkɔɪn dəˈbeɪsmənt/
act of decreasing the amount of precious metal in a coin, while continuing to circulate it at face value