Don’t get suspended: Principle vs. principal

On moral grounds alone, writers ought to properly use principle and principal.

Principle means “a basic truth or belief”: Liberty is among the principles the United States was founded upon. It is always a noun.

Principal refers to “something of primary importance.” It could be the guy who heads the school (The principal gave the naughty student a detention.). It might be money in a loan (The principal on his car came to several thousand dollars.). It could describe why something was done (The principal reason he retired from his job was frustration with his boss.). Note that it can be both a noun and an adjective.

So don’t ever get this wrong again, dear writer – or we’re sending you to the principal’s office.