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Is It Principle or Principal? How Are These Different?

Is It Principle or Principal? How Are These Different?

Using words adequately is as important when we speak as it is when we write. It is known that there are several words that are the same but used in variations of the English language. They change a letter or they are different in meaning but similar in their writing and could easily confuse us. This is the case of “principle” and “principal”, and here we will go over their differences, origin and use.

The word “principle” is only a noun, and it means to rule. It can also mean law or guideline. Now, “principal” is the director or head person from a school or business. The word “principal” is not only a noun, it can also be used as an adjective. 

Knowing the differences between these is important, while one refers to a guideline and the other one to the person that upholds them in a given institution. If you were to make a mistake while speaking, it is easy to correct but if it happens on a text that has been written and shared, one word could alter the entire intention or meaning of our writing. That is why here we will go over each in detail and offer examples for more clarity.

Origin And Definition Of The Word “Principle”

The word “principle” is connected to the Late Middle English from Old French and Latin word “principium”, which means “source” or “beginning”. Also, “principia” in the plural form which means “foundations”, which is also rooted in the word “princeps” which is translated to “first chief”.

principle word in dictionary

“Principle” can be defined as a fundamental assumption or a guiding belief. It can also be a set rule to help decide or function as a guide in times when a decision is needed. And it can also be interpreted as a moral rule, the compass by which people of certain honor or upbringing guide themselves to act in the world.

The word “principle” is also applied in nature and physics, in this instance, it refers to those basic ideas and fundamentals on how everything works. Nature, space, time, life, death.

Synonyms Of The Word “Principle”

Depending on where the word is being used there are several synonyms that could be taken into consideration as a replacement for “principle” in a sentence. Here are some of them:

  1. Tenet
  2. Essence
  3. Fundamental
  4. Philosophy
  5. Postulate
  6. Concept
  7. Theory
  8. Idea
  9. Basis
  10. Morals
  11. Integrity
  12. Credo
  13. Honor
  14. Conscience
  15. Standards

Origin And Definition Of The Word “Principal”

The root of the word “principal” is from Latin, from the word “principalis” which means “first in importance”. It is also connected to the meaning of “prince”, this is through the Latin “genitive principis” which means “first man”,” chief leader”, “rule” or “sovereign”.

It is also connected to the noun form or adjective of the root “primus” which means “first”.

The most common meaning and use of the word “principal” is to refer to the most important or most senior person in an organization. The direct meaning of the word, taking the root into consideration is “the first in order of importance”.

The way we probably hear it most these days is in reference to education institutions, either schools, institutes, or universities, since “the principal” or director is the go-to person for all affairs, regardless of how big or small in these institutions.

Synonyms Of The Word “Principal”

Just as “principle”, the word “principal” can be used in many contexts and also had many synonyms that could take its place in a sentence depending on this. Here are some of them:

  1. Main
  2. Chief
  3. Primary
  4. President
  5. Director
  6. Chairman
  7. Chairwoman
  8. First
  9. Dominant
  10. Foremost
  11. Manager
  12. Leader
  13. Key Person
  14. Boss
  15. Ruler

principal flourescent sign in brick wall

How Are “Principle” And “Principal” Different?

At this point, you have grasped both the meaning and use for each of these words, but for the sake of clarity the difference between “principle” and “principal” is that usually a “principle” is a quality or an object, we would never refer to a person as a “principle”. However, “principal” is both an adjective and a noun. We can refer to people and use the word “principal” to describe their role in an organization or chain of command.

So, “principle” is a rule, a guideline, and “principal” the person that makes sure others abide by those rules due to their role as key-person of an organization.

Examples Of “Principle” Used In A Sentence:

  1. He died for his principles, because of that his death will not be in vain.
  2. The principle of equality is starting to be a core value in most companies that are committed to offering equal opportunities for their employees regardless of their sex.
  3. It goes against my principles to cheat, kill, or steal. I was raised to respect and treat others as I want to be treated and respected.
  4. The principle of physics that governed the phenomena we observed are yet to be documented. It was something unprecedented that we witnessed here tonight.
  5. Tolerance should be a principle that guides everyone, so many accidents, family separation, and heartbreak could be avoided if we all practiced it more.
  6. In my opinion, the duty of every parent is to pass on to their children the best of their principles, and leave behind what others generation did that only caused pain for those around them.
  7. My principle is my faith. It is my moral compass and what tells me if I am walking the right path day in and day out.
  8. Their hypothesis took the principle of life as the basis to prove the accuracy of their findings.
  9. The laws and principles that rule our existence are right in front of us all the time. It is a lot like magic and how we only see the end game but the small details that make the illusion possible completely scape us.
  10. Do not ever question my principles and morals, it is the very core of who I am today.

Examples Of “Principal” Used In A Sentence:

  1. The principal suspect in this investigation was actually a judge of The Supreme Court.
  2. I had to come to my daughter’s school today because she was sent to the principal’s office for skipping classes for the past week.
  3. The principal reason behind the need for a vaccine is creating what is called “herd immunity”, this way those who are immuno-compromised or do not qualify due to underlying conditions can be protected from infection.
  4. If you watched him speak long enough, you would notice that the frown he made every time he stopped to think was the principal reason behind those wrinkles he has now.
  5. The principal person in my household is my mother, she is the oldest and the most fragile. We all revolve around making her comfortable and looking after her.
  6. I would have never guessed in my wildest dreams that I would be the principal of a department in a prestigious university. This promotion has completely taken me by surprise.
  7. The busiest city in the country is our capital city, the principal city. It is where everything happens, where the president lives, where the tourists go to experience a true colonial city in our time.
  8. Lacking time is just an excuse, the principal thing here is to acknowledge when you are making up excuses because deep down you know you no longer want to be with that person. It is painful to admit but the faster you realize this, the less hurt you will cause.
  9. The principal called me to her office to tell me I had been chosen as the designated class speaker for my graduation ceremony next week.
  10. Sugar, rum, and plantains are the principal source of exports for many of the countries in Panamerica and the Caribbean.

Antonyms Of “Principle” And “Principal”

Now that we have seen the examples of both of these words in sentences, it is useful to also see their opposites. Here are some antonyms for “principle”:

  1. Development
  2. Issue
  3. Action
  4. Operation
  5. Formation

Here are some examples of the antonyms for “principle”:

  • It was just an issue, nothing to be concerned about.
  • The action taken by the general was not a part of the military code.

Here are some antonyms for “principal”:

  1. Subordinate
  2. Minor
  3. Antagonist
  4. Back up
  5. Secondary

Here are some examples of the antonyms for “principal”:

  • He was nothing more than a backup, replaceable.
  • The subordinate must always follow the guidelines set by their leader.

right or wrong sign


In the examples above I am sure you noticed that when using the word “principle” in a sentence because it refers to a set of rules, guidelines or beliefs, it is common to use the plural form of the word by adding an “S” when using it in a sentence. Unless there is one single principle that is being referred to in the sentence.

In that same way, when we use the word “principal” in a sentence, because of its use as an adjective and a noun at the same time it is common to see it preceded by “the”.

That is all for now. With these “principles” we have shared with you and the examples for proper use of these words, you are certain to be the “principal” in the proper use of these words going forward.