Unsubordinated Debt
A loan or security that ranks above other loans or securities with regard to claims on assets or earnings. Also known as a senior security.
Investopedia Commentary
In the case of default, creditors with unsubordinated debt would get paid out in full before the junior debt holders. Therefore, unsubordinated debt is less risky than subordinated debt.
See also: Absolute Priority, Bankruptcy, Bond, Debt, Junior Security, Loan, Senior Security, Subordinated Debt