When writing an academic paper, it’s quite common to stumble upon commonly confused words. These words affect the quality of your paper because in academic writing you need to have precise and clear language to convey your arguments. Words like “principle” and “principal” cause confusion because they have nearly the same spelling. Thus, many use them interchangeably even though they have different meanings.
Definition of “principle vs. principal”
“Principle” and “principal” differ only by the two last letters, which is why they represent some of the most often confused words in academic writing. While “principle” refers to a rule, law, guideline, or fact, the word “principal” is the headmaster of a school or a leading person in a company. The word is also an adjective that means first, original, or most important.
Principle
… is a noun used to refer to a code, law, guideline, fact, or an underlay quality that motivates one’s behaviour.
Principal
… is a noun and adjective referring to a person in a leading position or something being the most important.
It is important to focus on the surrounding context to distinguish between the two words. To remember the difference, you can think of the “principal” as your “pal”.
Using the word “principle”
The word “principle” is only used as a noun. This will be outlined in the following.
“Principle” as a noun
The word “principle” typically functions as a noun in English grammar. The three example sentences will illustrate how to use the noun “principle” in a sentence.
Examples
- The principle of equality is a fundamental aspect of democracy.
- My guiding principle in life is to always treat others with kindness and respect.
- We must uphold the principles of justice and fairness in our society.
Tip for using “principle” correctly
Synonyms of the word “principle” can help remember how to use it in a sentence more efficiently. In the following, there will be four synonyms illustrating the meaning of “principle” in a sentence.
| Synonyms | Examples |
| Doctrine | The principle of karma states that one's actions determine their future. |
| The doctrine of karma states that one's actions determine their future. | |
| Law | The principle of gravity means objects will autumn to the ground if dropped. |
| The law of gravity means objects will autumn to the ground if dropped. | |
| Rule | The golden principle states that one should treat others as they wish to be treated. |
| The golden rule states that one should treat others as they wish to be treated. | |
| Tenet | One principle of democracy is that everyone has the right to vote. |
| One tenet of democracy is that everyone has the right to vote. |
Using the word “principal”
The word “principal” is used as a noun and as an adjective. This grammatical function will be outlined in the following subheadings with examples.
“Principal” as a noun
“Principal” can be used both as a noun and an adjective in English language grammar. As a noun, it typically refers to a person who holds a high position of authority, such as the head of a school or a company.
Examples
- The principal of the school is responsible for ensuring a safe learning environment.
- I need to speak to the principal about an issue with my child’s schedule.
- The principal of the company is retiring this year.
“Principal” as an adjective
“Principal” can also be used as an adjective grammatically. As an adjective, it often describes something that is most important or influential, such as a principal ingredient in a recipe.
Examples
- The principal reason for the company’s success is its innovative approach to marketing.
- The principal ingredient in this dish is fresh basil.
- The police determined that speed was the principal cause of the accident.
Tip for using “principal” correctly
Using synonyms can help distinguish between the meaning of “principle” and “principal”. Since “principal” can be used as a noun and adjective, the four following synonyms will be divided into two sentences using the noun “principal” and two using the adjective “principal”.
| Synonyms | Examples |
| Director (noun) | The principal of the department is retiring next month. |
| The director of the department is retiring next month. | |
| Head (noun) | The principal of the organization is responsible for setting strategic priorities. |
| The head of the organization is responsible for setting strategic priorities. | |
| Main (adj.) | The principal goal of the project is to increase efficiency. |
| The main goal of the project is to increase efficiency. | |
| Primary (adj.) | The software’s principal function is to manage inventory. |
| The software’s primary function is to manage inventory. |
Test yourself!
Practice sheet
To test your ability to differentiate between “principle” and “principal”, complete the 10 sentences by filling in the blank spaces. Afterward, refer to the second tab for the correct answers to confirm your comprehension.
- The _____ of free movement is a key feature of the European Union.
- The _____ actor in the film was nominated for an Academy Award.
- The _____ purpose of tax treaties is to prevent double taxation.
- The _____ reason for my decision to move was to be closer to my family.
- The _____ employer of a temporary worker is responsible for their working conditions.
- The _____ of proportionality requires that the punishment fits the crime.
- In language learning, the _____ aim is to develop proficiency in all skills.
- A company’s _____ place of business often determines its tax jurisdiction.
- The Constitution is based on the _____ of checks and balances.
- The UN Charter upholds the _____ of self-determination for all peoples.
- The principle of free movement is a key feature of the European Union.
- The principal actor in the film was nominated for an Academy Award.
- The principal purpose of tax treaties is to prevent double taxation.
- The principal reason for my decision to move was to be closer to my family.
- The principal employer of a temporary worker is responsible for their working conditions.
- The principle of proportionality requires that the punishment fits the crime.
- In language learning, the principal aim is to develop proficiency in all skills.
- A company’s principal place of business often determines its tax jurisdiction.
- The Constitution is based on the principle of checks and balances.
- The UN Charter upholds the principle of self-determination for all peoples.
FAQs
“Principle” refers to a general rule, law, or belief that guides behaviour, while “principal” means a person or thing that holds a leading or high position or the primary amount of money owed on a loan.
There are a few tricks that can help you remember the difference between “principle” and “principal”:
- One way to remember this is to think of the word “pal” in “principal.” A principal is your pal, somaeone who is there to help to guide you.
- Another trick is to remember that “principle” has a “le” in it, just like “rule.” Both words refer to guidelines or concepts.
“Principle” refers to a general rule, while “principal” means a person or thing that holds a leading or high position.
Examples
- The company’s principal investor is a wealthy entrepreneur. (“principal” as a noun, meaning a person of high importance)
- The principle of equal opportunity is enshrined in law. (“principle” as a noun, meaning a general rule or concept)
