驢打滾

Simplified: 驴打滚

lǘdǎgǔn ㄌㄩˊ ㄉㄚˇ ㄍㄨㄣˇ

    • usury with compounding interest
    • debt that grows ever larger

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
donkey rolling
Meaning
A form of usury where unpaid interest is added to the principal and keeps compounding, growing ever larger.

Sources