Some people get confused with the terms principal and principle. This is understandable since the two words not only look similar but also sound the same. However, in terms of meaning and use, these two are very distinct from each other.
As a noun, the word principal refers to “the person with the highest authority or most important position in an organization, institution, or group.” This is particularly evident among educational institutions or schools.
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Principal can also be used as a noun denoting “a sum of money lent or invested on which interest is paid.”
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Junior Mining Network“Under the standard student loan repayment plan, payments are calibrated so that the principal always equals zero at the end of the repayment period.”
Forbes“By reducing the debt, it allows more of every future payment to go to principal and less to interest.”
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The word principal can also be used as an adjective which means “first in order of importance.”
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The Drum“The principal guest on the evening was Barrie Crossley who was accompanied by the Furness and South Lakeland group chairman Peter Schofield.”
The Westmoreland Gazette“He was a principal benefactor of the first Irish Famine memorial in Cambridge, Massachusetts, which was dedicated in July 1997 by former Irish President Mary Robinson.”
IrishCentral
On the other hand, the term principle is used as a noun to refer to “a fundamental truth or proposition that serves as the foundation for a system of belief or behavior or for a chain of reasoning.”
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One way to distinguish between the terms is to remember that a principle refers to a rule or standard, while principal as an adjective means the most important and as a noun refers to the most important person in a particular group or organization.