A stock brokerage firm has agreed to provide secured debt to Jamie's business. Jamie has pledged his warehouses to the stock brokerage firm. What is this process of pledging a property in exchange for a debt known as

It's a collateral which is a borrower's pledge of specific property to a lender, to secure repayment of loan or debt. The collateral serves as a lender's protection against a borrower's default and so can be used to offset the loan if the borrower fails to pay the principal and interest satisfactorily under the terms of the lending agreement.