What Is Compounding?

Today, we are going to talk about building. But don’t worry. You won’t need to get out a hammer and nails because we are going to be building words. And what are we using to build words? Other words!

In English, we often create cool new words by mashing two or more words together. For example, we can take the word peanut and combine it with the word butter to make peanut butter. Delicious! Or we can take the word monkey and fasten it to the word wrench to make monkey wrench. Handy! Or we can add together right and angle to make a right angle. Algebraic!

Making new words is a lot of fun, so let’s keep going and learn about all the different ways we combine words together as we explore the grammatical concept of compounding.

What is compounding?

In grammar, compounding, also called composition, is when two or more words are combined together to form a new word. For example, the word underground is a combination of the words under and ground. In English, compounding is used to form words belonging to four common parts of speech: nouns, verbs, adjectives, and adverbs.

Most of the time, compounding creates a word or phrase that means something different than the meanings of the words used as “ingredients.” For example, the word bluebird refers to specific species of songbirds whereas the separate words blue bird refer to any bird with blue feathers. As another example, the adjective old school refers to supporting traditional methods or values and doesn’t refer to ancient scholarly buildings.

Compounding often involves combining different parts of speech together. For example:

  • Noun + Noun = gatekeeper
  • Verb + Noun = spoilsport
  • Adverb + Verb = overestimate
  • Adjective + Noun = green thumb
  • Verb + Preposition = give in

New compound words emerge every day in English. The rise of the internet and the growing popularity of social media has led to a huge number of new compounds to describe things we see online. The compounds social media, website, viral marketing, doomscrolling, and selfie stick are just a few examples.

The different types of compounds

Typically, compounds are usually divided into three different types. Often, the way the compounds are labeled will depend on which dictionary or grammar resource that you use. It is also possible for a compound to be considered more than one type. Generally, if a specific compound doesn’t appear in a dictionary at all, the typical pattern is that it will be hyphenated.

Closed compounds (Single words)

Closed compounds are compounds that consist of two words combined together without a space in between. Some examples of closed compounds include blackboard, sweatshirt, backstroke, undercut, horseshoe, desktop, and smartphone.

Open compounds (Multiple words)

Open compounds consist of two words with a space in between them. Examples of open compounds include air conditioner, guardian angel, French toast, spray paint, and cream cheese.

Hyphenated compounds

The last type of compound is formed by connecting two or more words together using hyphens. Newer compounds and/or compounds that don’t appear in dictionaries are often written as this form of compound. Examples of hyphenated compounds include fat-free, dark-skinned, merry-go-round, two-faced, tractor-trailer, and stay-at-home.

Learn all about how to use hyphens here!

Compounds in different parts of speech

Examples of compounds can be found in four of the most commonly used parts of speech: nouns, verbs, adjectives, and adverbs.

We will briefly look at each of these different types. If you want to explore each one in more detail, we have provided an extensive guide to three of the types of compound in the links below:

Examples of compound nouns

Closed: basketball, headphones, rowboat, rainforest, toothpaste, frostbite
Open: tennis shoe, fabric softener, gym shorts, banana split, peanut butter
Hyphenated: jack-in-the-box, city-state, sister-in-law, will-o’-the-wisp

Examples of compound verbs

Closed: blackmail, blindside, overshoot, brainwash, underperform
Open: turn back, check in, mull over, play up, double down
Hyphenated: gift-wrap, baby-sit, double-check, criss-cross, cherry-pick

Examples of compound adjectives

Closed: seasick, waterproof, overpowered, downtrodden, homemade
Hyphenated: red-faced, white-collar, sun-dried, cold-blooded, last-minute

Open compound adjectives are less common and often take the form of an open compound noun being used as an adjective. For example:

  • high school student, jump rope competition, hot dog bun

Often, an -ly adverb is combined with a past participle to form an adjective phrase. Depending on the grammar resource, these formations may be considered to be open compound adjectives. For example:

  • overly simplified explanation, brightly lit room, barely audible sound, easily missed detail

Examples of compound adverbs

Closed: therefore, hereafter, sometimes, whenever, overnight
Open: upside down, inside out, early on, almost always, over and over
Hyphenated: topsy-turvy, in-house, self-consciously

Examples of compounding in sentences

There are lots and lots of compound words out there. We use compound words to refer to many common things, so you are likely to come across and use a ton of compound words in your everyday speech. Let’s look at just a few examples of how we typically use compound words in our sentences.

  • I asked for another serving of egg rolls.
  • The bowl was filled with blueberries and sunflower seeds.
  • She held a block party at her beach house.
  • Because he had a headache, he called a timeout during the football game.
  • The major general shored up the gaps in the front line with more infantrymen.
  • She double-clicked the mouse while mashing buttons on the keyboard to try to fix her desktop computer.
  • My stepsister owns a workshop that makes wristwatches, timepieces, and grandfather clocks.

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Do you have questions about compound vs. collective nouns? We have all the answers here.

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