The principal amount of a bond that is repaid at the end of the loan term is typically referred to as the "face value," "par value," or simply the "principal" of the bond.

In the context of bonds, the principal amount represents the initial amount borrowed by the issuer of the bond and is the amount that the issuer promises to repay to the bondholder at maturity. It's the amount on which the periodic interest payments are calculated, and it's the amount that bondholders expect to receive back when the bond matures, assuming the issuer doesn't default on its obligations.

The terms "face value" and "par value" are often used interchangeably with "principal" to refer to the nominal value of the bond, which is typically stated on the bond certificate. This value is what the bondholder expects to receive when the bond matures, regardless of the price at which the bond was originally sold or its market value during the term of the loan.