What are Compound Words and How to Use Them Correctly?

The English language is full of compound words, so understanding them is an important part of the learning process. Whether you’re proficient in English or a beginner, you’re constantly using them in your everyday language.

That’s why you should be able to recognize them easily, which is actually way simpler than it sounds.

You may not be aware that you’re using them because some types of compound words are easier to recognize than others. But before explaining each type separately, let’s see what compound words are.

What is a Compound Word?

In other words, you combine two or more words to produce one new word with a unique meaning.

For example, “water” and “melon” have their own meanings when used separately. But, if you join them together, you get a new word with an entirely different meaning—“watermelon.” This is why watermelon is a compound word.

But, this is just one example of a compound word. There are a few types of compounds, and each of them is formed differently. Let’s learn more about them.

Types of Compound Words

“Watermelon” is a closed compound word, so that’s one of the three types of compound words. The others are open compounds and hyphenated compounds. Here’s more about each type of compound.

Closed Compound Words

Did you even know “watermelon” is a compound word? Although it’s one word, it was originally created by combining two words. The English language is full of closed compounds like “watermelon,” which have been so commonly used that it’s hard to guess they are actually made up of two words.

The thing is most closed compounds used to be written as two words with a space or hyphen between them. But, the ones that were used a lot eventually became one word.

Other examples of closed compound words include blueberry, aircraft, meatballs, cardboard, cupcakes, bedroom, grandparent, football, fireman, waistcoat, etc.

Open Compound Words

As opposed to closed compounds, open compound words are still written as two words with a space between them. This, however, makes them more difficult to recognize. The only way to distinguish them from two regular words standing next to each other is if they create a new word with a unique meaning.

These compounds are usually nouns consisting of a modifying adjective and another noun, or two nouns.

For example, “ice cream.” This compound is a noun consisting of the two nouns “ice” and “cream.” Both nouns have a different meaning than “ice cream” when used separately. But when you read them together, you’ll almost always think about the dessert called “ice cream” rather than just “ice” and “cream.”

Other open compounds include full moon, hot dog, living room, life jacket, school bus, mobile phone, coffee mug, diner table, post office, high school, etc.

Hyphenated Compound Words

Hyphenated compound words are formed by joining two or more words together with a hyphen. Most of the time, they are preceding a noun they modify, in which case they are considered modifying adjectives. But, they can also be nouns and stand independently in the sentence.

For example, the hyphenated compound “full-time” modifies the noun that follows it and has a different meaning than “full” and “time.” Whether it’s a full-time writer, a full-time worker, or a full-time freelancer, the compound “full-time” modifies the nouns “writer,” “worker,” and “freelancer.”

Other hyphenated compounds include father-in-law, mother-in-law, Merry-go-round, long-term, one-half, up-to-date, over-the-counter, check-in, two-fold, sixty-seven.

Compound Words in Sentences

Here are more examples of the three types of compound words used in sentences:

My bedroom is bigger than my living room.
(Bedroom – a closed compound; living room – an open compound).

Firefighters worked hard to extinguish the fire at the high school gymnasium.
(Firefighters – a closed compound; high school – an open compound).

Her mother-in-law works at the post office.
(Mother-in-law – hyphenated compound; post office – open compound).

Video examples: