There are multiple definitions - click on the translation that matches your context.

Mandant

Substantiv

full

principal

noun

Definitions of principal

English

a person who uses another to act as his or her representative

An agent cannot bind its principal when it exceeds (= goes beyond) the limits of its authority.

English

the original sum of money loaned under a loan agreement

The proposed legislation will help investors recover principal money secured by a charge on land or personal property.