usury
noun
[ ˈjuːʒ(ə)ri ]
• the action or practice of lending money at unreasonably high rates of interest.
• "the medieval prohibition on usury"
Similar:
extortionate moneylending,
payday lending,
loan-sharking,
shylocking,
Origin:
Middle English: from Anglo-Norman French usurie, or from medieval Latin usuria, from Latin usura, from usus ‘a use’ (see use).