Gresham's law

noun

Gresh·​am's law ˈgre-shəmz- 

: an observation in economics: when two coins are equal in debt-paying value but unequal in intrinsic value, the one having the lesser intrinsic value tends to remain in circulation and the other to be hoarded or exported as bullion

broadly : any process by which inferior products or practices drive out superior ones

Word History

Etymology

Sir Thomas Gresham

First Known Use

1858, in the meaning defined above