money lent at daily interest
Historical term for a high-interest loan where interest was calculated daily, often associated with Edo-period moneylending. The kanji 烏 (crow) may derive from the image of crows returning to their nests at dusk, suggesting the daily repayment cycle.
In the Edo period, there existed high-interest loans called karasugane, with daily interest.
The word karasugane is now only seen in historical documents.
The term 烏金 (からすがね) literally means 'crow money'. The exact origin is uncertain, but it is often explained as deriving from the practice of crows returning to their nests at dusk, metaphorically linking to the daily repayment cycle of the loan. This is a historical term with no clear modern equivalent.