What is the difference between principal and principle?

Principal is a person (the head of a school) or an adjective meaning main or most important. Principle is always a noun meaning a rule, law, or belief.

How do I remember principal vs principle?

The classic trick: the princi pal is your pal (a person). And a princi ple is a ru le — both end in -le.

Is it ’in principle’ or ’in principal’?

In principle — the fixed phrase means “as a general rule” or “in theory,” so it uses the rule word: We agree in principle, but the details need work.

Level: B2

Principal vs Principle

Principal (a school’s head; main) and principle (a rule or belief) sound identical, and even native speakers mix them up in writing. Two memory tricks solve it — then practice below.

🔍 Confused words · pair 36 of 54 ⏱ about 5 minutes 🔊 every sentence has audio

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For Matching Game quizzes, choose sentences that include more than one of the words below. If you pick sentences with only one word, the quiz will automatically add a sentence using another word.

Principal – the head of a school; main, most important.
The ______ welcomed the new students. – principal
She was called to the ______’s office. – principal
Our ______ announced a new school schedule. – principal
Coffee is the country’s ______ export. – principal
The ______ reason for the delay was bad weather. – principal
Tourism is the island’s ______ source of income. – principal
The ______ gave a speech at graduation. – principal
Safety was their ______ concern. – principal
The ______ hired three new teachers. – principal
Rice is the ______ crop in this region. – principal
Students met the ______ on the first day. – principal
The ______ character of the novel is a young doctor. – principal
Her ______ goal is to finish college. – principal
The ______ suspended the student for a week. – principal
Oil remains the ______ driver of their economy. – principal
Parents wrote a letter to the ______. – principal
The ______ cause of the fire was faulty wiring. – principal
Our school ______ retires this year. – principal
The ______ cities of the region are on the coast. – principal
He was promoted from teacher to ______. – principal
Principle – a rule, law, or personal belief (always a noun).
Honesty is her guiding ______. – principle
The machine works on a simple ______. – principle
He refused to lie as a matter of ______. – principle
We agree in ______, but the details need work. – principle
The law is based on the ______ of equality. – principle
She never breaks her ______ of always telling the truth. – principle
Treating others fairly is a basic ______. – principle
The experiment demonstrates a key ______ of physics. – principle
It’s not about the money — it’s the ______. – principle
Democracy rests on the ______ of free elections. – principle
He is a man of strong ______. – principle
The first ______ of cooking is to taste as you go. – principle
Their business follows one simple ______: the customer comes first. – principle
The ______ behind the vaccine is easy to explain. – principle
She stood by her ______ even under pressure. – principle
Supply and demand is a basic ______ of economics. – principle
On ______, he never borrows money. – principle
The design follows the ______ that less is more. – principle
Each lesson teaches one grammar ______. – principle
The judge explained the legal ______ behind the ruling. – principle

Frequently asked questions

What is the difference between principal and principle?: Principal is a person (the head of a school) or an adjective meaning main or most important. Principle is always a noun meaning a rule, law, or belief.
How do I remember principal vs principle?: The classic trick: the principal is your pal (a person). And a principle is a rule — both end in -le.
Is it ’in principle’ or ’in principal’?: In principle — the fixed phrase means “as a general rule” or “in theory,” so it uses the rule word: We agree in principle, but the details need work.