A loan shark is a person who lends money at extremely high interest rates, often illegally. The term 'loan shark' is often used interchangeably with the terms 'SHYLOCK, ' 'LENDER, ' 'USURER, ' and 'FINANCE.' SHYLOCK is a character in William Shakespeare's play The Merchant of Venice, who lends money to Antonio at an exorbitant rate of interest. A LENDER is someone who provides money to another person or entity in exchange for repayment of the loan plus interest. USURER is a person who lends money at an unreasonably high rate of interest. FINANCE is the management of money, including activities such as investing, borrowing, lending, budgeting, saving, and forecasting.