So this issue came up while tutoring today and as soon as I brought it up with my student, a fellow tutor said “I just went over that with my student!” At that point, I knew it was time to make a Grammar Quick Fix. Although they’re homonyms (sound alike), they have very different meanings. Let’s find out what they are!
If you’re a native English speaker, you may have been taught at a young age, “The principal is your pal!” This memory hook is effective because of the “pal” at the end, and the sense of a “pal” being your friend. This is true to a certain extent. Principal is certainly a noun, meaning someone who is most highly ranked and very important. This word is most commonly used for the person in charge of a school, such as a high school or middle school. Principal can also be used as an adjective, meaning the larger or more important thing. For example, “I’m paying off the principal loan.” This would mean the larger loan. It’s frequently used as an adjective.
Principle is ONLY a noun, unlike principal. It works with laws and doctrines. For example, “Labor unions fought hard to for the principle of equality.” If you’re not talking about a law or societal, moral, or legal doctrine, you won’t use principle.