Binomials, Compound Words, and Collocations


Friendship is a beautiful thing...


Just like us humans have close friends, there are words in our language that are best friends too.

There are three types of these best friend words

Let us learn more about these buddies and what makes their friendship so strong.

Let us start with our first word buddies… Collocations!


There is an unspoken understanding between the words in a collocation.

This is because collocations are simply words in our language which normally tend to go together.

For example, “heavy rain” is a collocation because we generally use these two words together.

We do not say “weighty rain” or “large rain”.

We can have collocations made of more than two words too.

For example, “wear and tear”, “once upon a time”, “aid and abet”, “deep blue sea”.

We use collocations to make our language seem more natural, and to pack meaning into our sentences.

Let us move on to the second group of best friend words… Binomials!


A Binomial is a pair of words which are normally linked by a conjunction or preposition.


Together, they form a unit of meaning.

For example, “safe and sound” is a binomial pair which is linked with a conjunction.

And “side by side” is an example of a binomial pair linked with a preposition.

There are two different types of binomials, Reversible Binomials and Irreversible Binomials.

A Reversible Binomial is a binomial pair in which the order of words can be switched around without being confusing or awkward.

For example, we can say “tired and hungry” or we can say “hungry and tired”, and in both cases, it sounds fine.

Also, within Reversible Binomials, there are two special types called Synonymous Binomials, and Echoic Binomials.

In a Synonymous binomial, the two linked words are different, but have the same meaning.

For example, “pain and suffering”. Here, “pain” and “suffering” are synonyms of each other.

In an Echoic binomial, the two linked words are the same. For example, “stronger and stronger”.

Both Synonymous and Echoic binomials are used to emphasize things.

In the second type of binomials, Irreversible Binomial...

We cannot change the order of the linked words, because it would sound strange or confusing.

For example, we can say “lost and found”, but it would sound awkward if we said “found and lost.”

Another example is “dos and don’ts.” It would sound strange if we said “don’ts and dos” instead.

So, Irreversible Binomials cannot be changed because these are words which generally go together...

Thus, we can say that all Irreversible Binomials are also Collocations, since they are words which tend to go together.

But not all Collocations are Irreversible Binomials.

Let us move on to our last type of friendly words, Compound Words!


A Compound Word is formed when two words come together to create a new meaning.

For example, “ice cream” is a compound word.

There are three types of compound words, Closed, Open, and Hyphenated.

A Closed Compound Word is formed when we take two separate words and join them to create a new word .

For example, “notebook”.

Other examples of closed compound words are “birthday”, “railway”, “login”, “online”.

The second type of Compound Words is called Hyphenated Compound Words.

These are separate words which we join together with hyphens to make one unit.

For example, “sugar-free” is a Hyphenated Compound Word.

We can also sometimes join three words together to make a Hyphenated Compound Word. For example, “brother-in-law”.

Finally, let us see what an Open Compound Word is...

An Open Compound Word is when we write two separate words, but they form a single unit of meaning.

For example, “drawing room”.

We can identify open compound words based on whether the two words are commonly used together.

For example, “full moon” is a compound word, but “bright moon” is not.

From this, we can see that Open Compound Words are also Collocations...

Because they are separate words that generally go together.

For example, “fast food” is an open compound word because two separate words are coming together to refer to one thing.

But “fast food” is also a collocation because we can only say “fast food” and not “quick food” or “fast snacks”.

In other words, “fast food” is also a collocation because it is two words which normally go together, and changing the words makes it sound strange.

Let’s do a quick recap.


A binomial is a pair of words which are linked by a conjunction or preposition to form a unit of meaning.

A compound word is when two or more words come together to form a single unit, without conjunctions or prepositions.

A collocation is two or more words which usually go together.

All irreversible binomials are collocations, but not all collocations are irreversible binomials.

All open compound words are collocations, but not all collocations are open compound words.

That’s all Folks!