banker's discount
noun[C]
BANKING,FINANCEukusthedifferencebetween theamountshownon abillofexchange, etc. that acustomersendsto abankforpayment, and theamountthat thecustomerreceives, after thebankhas takenitspayment:
The banker'sdiscountiscalculatedat acertainrateofinterestperannumon theamountof thebillfor the unexpiredperiod.