Principal vs. Principle: The Rules On The Difference

Is the head of a school called a principal or a principle? These two words are frustratingly similar, leaving even the most experienced English speakers to second-guess which word means what.

In this article, we’ll discuss the distinct meanings between these easy-to-confuse terms—and leave you with a little trick to help differentiate between your principals and your principles.

What is the difference between principal and principle?

A principal is “a chief or head, particularly of a school.” Principal can also be used as an adjective meaning “first or highest in rank, importance, or value,” as in The principal objective of this article is to teach you the difference between two words.


WATCH: How This School Principal Uses Words To Make Change Happen


A principle, on the other hand, is “rule of action or conduct” or “a fundamental doctrine or tenet.” Principle is often associated with and used as a synonym for moral, meaning “of, relating to, or concerned with the principles or rules of right conduct or the distinction between right and wrong.”

As you may have guessed, principal and principle are etymologically related. Principal stems from the Latin prīncipālis, a word meaning “first, chief.” Principle comes from prīncipium, meaning “beginning, origin, starting point, basis.” Both terms can ultimately be traced to the Latin word prīmus, meaning  “first, foremost,” hence the English prime.

How to remember if you should use principal or principle

If you find yourself having trouble choosing between principal and principle, think about the context. Use principal in reference to a person who is in leadership or to describe the importance of something; use principle to refer to a standard, rule, or guiding belief.

One popular mnemonic device to remember this difference is the isolation of “pal” from principal. The principal of your school is your “pal” … ideally.

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