Collins English-English Dictionary

principal ['prɪnsɪp^əl]

1. 1. adj [prenominal] first in importance, rank, value, etc; chief

2. 2. adj denoting or relating to capital or property as opposed to interest, etc

3. 3. n a person who is first in importance or directs some event, action, organization, etc

4. 4. n (in Britain) a civil servant of an executive grade who is in charge of a section

5. 5. n [law] a person who engages another to act as his agent

6. 6. n an active participant in a crime

7. 7. n the person primarily liable to fulfil an obligation

8. 8. n the head of a school or other educational institution

9. 9. n (in Scottish schools) a head of department

10. 10. n [Finance] capital or property, as contrasted with the income derived from it

11. 11. n the original amount of a debt on which interest is calculated

12. 12. n a main roof truss or rafter

13. 13. n [music] the chief instrumentalist in a section of the orchestra

14. 14. n one of the singers in an opera company

15. 15. n either of two types of open diapason organ stops, one of four-foot length and pitch and the other of eight-foot length and pitch

16. 16. n the leading performer in a play

17. 17. n [Etymology] C13: via Old French from Latin principalis chief, from princeps chief man, prince