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English definition of “principal”


adjective [not gradable]  /ˈprɪn·sə·pəl/ us  

principal adjective [not gradable] (MAIN)

first in order of importance: Iraq’s principal export is oil.


noun  /ˈprɪn·sə·pəl/ us  

principal noun (PERSON)

[C] a person in charge of a school

principal noun (MONEY)

[C usually sing] an amount of money that is lent, borrowed, or invested, apart from any additional money such as interest
(Definition of principal from the Cambridge Academic Content Dictionary © Cambridge University Press)
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