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October 13, 2023

All about compound words: open, closed, and hyphenated

When two words combine to form one, do you put a space between the words? Or better yet, is there supposed to be a hyphen separating the words? While we know some compound words like “baseball” and “blackberry” are typically lumped into one word, it can be tricky to know when exactly to add a space or hyphen. Learn about open, closed, and hyphenated compound words and when to use which.

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What is a compound word?

A compound word is a word or phrase that is created by pushing two individual words together. The meanings of the combined words are often related to the definition of the new word, but sometimes they can have different meanings. For some compound words, specifically with open and hyphenated compound words, three or more words can be used to create one word. The three types of compound words are open, closed, and hyphenated, and we will go through each type to show you how they work.

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What is an open compound word?

An open compound word is a compound word that has a space in between the two words. Although open compound words are separated by a space, they are recognized as one word because they form a new meaning. Here are some examples of open compound words.

  • Ice cream
  • Mashed potatoes
  • Hot pot
  • Deviled eggs
  • Ramen noodles
  • Turkey burger
  • Chicken salad

Open compound words can be made up of more than two words. For instance, the word “peaches and cream pie” uses four separate words to create a whole new one.

“The meanings of the combined words are often related to the definition of the new word, but sometimes they can have different meanings.”

What is a closed compound word?

A closed compound word is a word that is created by combining two individual words. Unlike open compound words, closed compound words do not have a space separating the two words. While open compound words are usually nouns, closed compound words can be found in almost every part of speech. Here are some examples of closed compound words.

  • Cheeseburger
  • Milkshake
  • Breakfast
  • Grapefruit
  • Soybean
  • Buttermilk
  • Cupcake

Some open compound words can also contain closed compound words within them. The words “strawberry soda” and “gingerbread house” both start with closed compound words and are followed by another individual word to create a new, open compound word.

What is a hyphenated compound word?

Hyphenated compound words are comprised of two or more individual words and are separated by a hyphen. Knowing when to add a hyphen can be tricky, but it’s easier if you remember that a compound adjective, or a compound word that modifies a noun, is usually hyphenated. Here are some examples of hyphenated compound words that can come before a noun:

  • Old-fashioned donut
  • Freeze-dried mango
  • Deep-fried wings
  • Cage-free egg
  • Medium-rare steak
  • Self-serving buffet
  • Low-sodium soy sauce

Hyphenated compound words can also be nouns themselves. Here are a few examples of hyphens in compound nouns.

  • My mother-in-law makes the best empanadas ever!
  • He is such a know-it-all when it comes to cooking pasta.
  • With so many skills, she really is a jack-of-all-trades.

Can open, closed, and hyphenated compound words be used interchangeably?

Some compound words can be spelled with a space, hyphen, or no space at all and still have the same meaning. A good example is the word “warm up,” which can also be spelled as “warmup” or “warm-up.” However, there are several instances of compound words that have completely different meanings if a space or hyphen is added. The word “makeup” can mean cosmetics or the way things are put together, but “make up” is a verb that means to make a decision, to come up with something, or to make amends with someone. “Toss-up” is a noun that means both teams have an even chance, and “toss up” is a verb that means to throw something in the air.

If you’re not sure whether to use a space or a hyphen for a compound word, an editing tool can help you pick the right spelling. Find more writing tips to get help with grammar, spelling, and editing to become a better writer.

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