1. most important; main

1. the head of a school
2. a sum of money that is invested or lent, on which interest is paid
Usage: finance
3. a person who has the highest authority or is in the leading position

Examples

• The principal reason for the delay was bad weather.
• Our school principal announced new policies at the assembly.
• She invested the principal amount in government bonds.
• The principal actor in the play gave an outstanding performance.
• The loan’s principal must be repaid within five years.
• Safety is our principal concern during the construction project.
• The principal of the firm made the final decision.