Someone sent me this question on another website.  As I sometimes do, I will post the question and answer here.

One more question, what`s the difference between important, essential, significant, critical, crucial and vital? When I write essays, I(or most Englishe learners) think use more different words is better than using one word repeatedly.

First, I need to make a correction.  “. . . I (and most other English learners) . . .”

I will take the words one that time and try to give them simple English definitions.  These words are all quite similar but are used in different situations and mean slightly different things.  Some mean essentially the same thing.  As you will notice, I will give you important examples as I write this blog and used these words.

Important: the word important is an important word to know.  It is not particularly critical that you learn at and not vital to this conversation.  But it is important.  If you had to you could live without this important word.  But it would be fairly difficult.  So important means it’s very nice to have and you’d like having at and it’s very useful.  It might be significant to your writing but it’s not absolutely essential, critical, crucial, or vital.

Essential: if it is essential it is more important than just being important.  You have to have it.  It is essential, critical, crucial, and vital.  You might have significant problems if an important part is missing on your airplane but any flight would be disastrous if an essential part was missing.  For example, the seats for the passengers are important but there not essential.  I once rode on a smoke jumper plane which had no seats.  It wasn’t exactly comfortable but it shows that seats are not essential.  The wings of the plane, on the other hand, are essential, critical, crucial, and vital.

Significant: if you want to be comfortable when you’re traveling it is important, but not critical, to carry a significant amount of money with you.  It’s not crucial, but it is nice to have and quite important.  If you want to buy something at your destination it is critical and essential you have something of value with you but it doesn’t have to be money.  It’s important to have money but a small block of gold will work if that’s all you have.  Money is not absolutely essential.  Having a small amount of money is important for most travelers, but having a significant amount of money is really nice.

Critical: when does something that is essential become critical, crucial, or vital.  Let’s get back on our airplane.  Having a pilot when you’re riding on a plane is fairly important and really essential.  But let’s say it’s a small plane with the pilot and three passengers.  The pilot has a heart attack and dies.  It is essential to have a pilot but now an essential part of the plane is missing.  Most people would consider that pilot fairly important but now he’s dead.  What are the three passengers going to do?  Now the problem is more than essential, things have gone to critical.  The passengers may have thought the pilot was essential and crucial as well as vital to their needs.  But it is critical that one of them take over for the pilot.  A critical need is an even stronger need than an essential one.  An essential one you might survive without.  A without a critical need supplied you’re going to die.

Crucial: so, how to be crucial on vital fit into this picture.  Usually these words are used in different situations.  You could use them in the above sentences in many places and say essentially the same thing, but these words are used more for special occasions.  The word crucial is often used for something that as much needed but not necessarily absolutely essential much like our pilot above.  For example, the pilot may have forgotten to check the oil in the engine.  Oil is necessary if you want a motor to run but is a crucial part of keeping a motor running.  It is essential that you make sure you have enough oil and you might get into a critical situation if you forgive this crucial ingredient.  The word crucial is more often applied to very important parts of things or even ideas.  You might leave out a crucial part of a speech and the audience would have a significant problem trying to understand the importance of what you’re saying.

Vital: vital is like the word vitality and is often associated with life.  If you’re baking a cake and you leave out the eggs you have forgotten a vital ingredient.  Eggs more than important in making a cake, they’re an essential ingredient and if you leave them out you made a significant error.

This is the end of this important lesson.  Do you have to learn it?  No, you won’t die if you don’t memorize it but learning how to use a variety of words with some more meanings is essential if you want to master a language.  You always make significant errors, so don’t worry about that.  It is not crucial that you get everything correct.  But you will give your writing and speaking more vitality if you learn the significant differences of the various shades of meaning.  All this is not absolutely critical because you can learn some important things as you go but it is crucial, it is vital, it is essential, and it is critical that you do something.  As you can see, these things are important.

One last comment is important in this conversation but not vital to your understanding.  Another editor told me, “Do not use the word significant in a scientific research paper and less you mean ‘statistically significant.’” I am a professional editor and writer.  I need to know how to use words correctly.  In my special field I can’t just say “the findings were significant” unless there is a P value associated with the comment.  If you’re not a scientist, don’t worry about this paragraph.  But I teach scientific writing so it is crucial I include this important point.