noun
second mortgage
A mortgage taken out on a property that already has an existing mortgage; the second mortgage is subordinate to the first.
二重抵当を設定すると、最初の抵当権者より返済順位が劣後する。
When you set up a second mortgage, its repayment priority is lower than that of the first mortgage holder.
Compound of 二重 (double, two-fold) and 抵当 (mortgage, pledge). The term is a direct calque from the English legal concept 'second mortgage'.