Meaning 1: The head of a school
* The principal addressed the students before the assembly.
* The new principal is known for her innovative teaching methods.
* We met with the principal to discuss our concerns about bullying.
Meaning 2: The most important part or element
* The principal reason for our success is teamwork.
* Honesty is a principal value in our family.
* The principal ingredient in this recipe is fresh tomatoes.
Meaning 3: A sum of money lent or invested
* We paid back the principal amount of the loan in full.
* The interest rate on the principal is quite high.
* The principal is invested in a high-yield savings account.
Meaning 4: A person who is primarily responsible for something
* The principal in the case was found guilty.
* The principal investigator is leading the research project.
* The principal architect designed the new building.
Remember: It's important to pay attention to the context of the sentence to determine which meaning of "principal" is intended.