principal

The person in charge of a school.

• The principal welcomed the new students.
• My parents met with the principal yesterday.
• She became principal of a small school.

Similar words: headteacher, headmaster, headmistress

Common phrases: school principal, principal’s office, assistant principal

A leading person in a business or a performer with a main role in an artistic group.

• The firm has three principals.
• He became a principal with the ballet company.
• All the principals attended the business meeting.

How to use it: principal of something (She is a principal of the architectural firm.)

Similar words: leader, head

Common phrases: company principal, ballet principal, principal of something

The original amount of money borrowed or invested, without interest or profits.

• The principal is ten thousand dollars.
• Each payment reduces the principal of your loan.
• Interest is calculated on the remaining principal.

Similar words: capital

Common phrases: repay the principal, principal and interest, outstanding principal

The person who leads a college or university and is responsible for its teaching and management.

• The principal welcomed the new students.
• Our college has appointed a new principal.
• The university principal spoke at the graduation ceremony.

Similar words: head

Common phrases: college principal, university principal, appoint a principal

A person or organization that another person acts for, especially in business or legal matters.

• The agent signed for her principal.
• An agent must follow the principal's instructions.
• The contract named both principals and their agents.

Similar words: client

Common phrases: act for a principal, principal and agent, disclosed principal

Main or more important than the others.

• Cost is our principal concern.
• Tourism is the island’s principal source of income.
• What was the principal reason for your decision?

Similar words: main, chief, primary, leading

Opposites: secondary

Common phrases: principal reason, principal aim, principal source

Chosen as the single standard value when a mathematical function could have several values.

• The principal square root of nine is three.
• Use the principal value of the logarithm.
• This graph shows the function’s principal branch.

Common phrases: principal square root, principal value, principal branch