Hyphens are incredibly helpful for clarifying meaning. Notice, for example, the difference in meaning between these two phrases: “hot water bottle” and “hot-water bottle.” In the first phrase, there is a bottle that is physically hot to the touch. In the second phrase, it’s a bottle that holds hot water. How can a reader know the difference? With the hyphen! Use hyphens to create compound adjectives, write two-digit numbers, attached prefixes, and connect words and numbers in other ways. If you want to be a good communicator, you must know how the hyphen works!

Terms You Need to Know to Use Hyphens

COMPOUND ADJECTIVES
A compound adjective is a word that is made up of two or more words that when combined act as a single adjective. These words are often joined together by a hyphen. Examples of compound adjectives include the following: well-behaved, doe-eyed, and single-handed.

PREFIX
A prefix is a word, letter, or series of letters that is placed in front of other words or letters that change the meaning of a word. Many words in the English language contain prefixes.

SUFFIX
A suffix is a word, letter, or series of letters that is placed after other words or letters. It is similar to a prefix in the way it changes the meaning of a word and is frequently used.

7 Ways to Use Hyphens

Create Compound Adjectives
Spell Two-Digit Numbers
Clarify Verbs with Prefixes
Join Prefixes to Capitalized Words
Join a Number to a Word
Join a Prefix to a Date
Separate Prefixes & Suffixes When Three Letters come in a Row

1. Create Compound Adjectives

DESCRIPTION
Sometimes you’ll want to describe something with multiple adjectives that combine to make a single adjective (for example, you might use “fast-paced” to describe your chemistry class; this adjective is two words, but it functions as a single adjective.) To create a compound adjective, you need a hyphen.

APPLICATION
To create a compound adjective, simply put a hyphen between the two or more words that combine to create the compound adjective.

EXAMPLE

Maribel’s favorite well-known author is J.K. Rowling.
(In this sentence, a hyphen is added between “well” and “known” to form a compound adjective.)

NOTE #1: Compound adjectives that use an adverb aren’t hyphenated. So if you say “the quickly eaten cheeseburgers,” you don’t need to put a hyphen between quickly (an adverb) and eaten.

NOTE #2: While compound adjectives usually consist of two words, you can technically have as many words as you need to create a compound adjective, with a hyphen between each word. For example, you might say, “It wasn’t until I finished that super-scrumptious-but-heart-attack-inducing brownie that I realized I should have just skipped dessert.”

2. Spell Two-Digit Numbers

DESCRIPTION
A hyphen needs to be used when writing two digit numbers. When two-digit numbers are spelled out rather than written numerically, a hyphen is used to connect the words that form the number.

APPLICATION
To use a hyphen to create a two-digit number, put a hyphen between the two words that make up the number.

EXAMPLE

The firemen of the Flamingo County Fire Department saved thirty-five people from the apartment complex.
(In this sentence, the number thirty-five is written out, so it needs a hyphen between the two numbers.)

3. Clarify Verbs with Common Prefixes

DESCRIPTION
A prefix is a word, letter, or series of letters that is placed in front of other words or letters that change the meaning of a word. A hyphen is used to clarify verbs that have common prefixes when there may be confusion over the meaning of the verb. For example, the difference in meaning between “re-create” and “recreate” is quite different.

APPLICATION
To use a hyphen to clarify verbs with common prefixes, put a hyphen between the prefix and the rest of the verb.

EXAMPLE

The mayor resigned after he re-signed his confession.
(In this sentence, there is potential confusion between the words “resigned” and “re-signed,” so the hyphen helps to distinguish the difference in meaning.)

4. Join Prefixes to Capitalized Words

DESCRIPTION
A prefix is a word, letter, or series of letters that is placed in front of other words or letters that change the meaning of a word. A hyphen is used to join these prefixes to words that are consistently capitalized.

APPLICATION
To use a hyphen to join a prefix to a capitalized word, put a hyphen after prefix and before the capitalized word.

EXAMPLE

Fred declared to his homeroom class that it was simply un-American to wear scarves.
(In this sentence, the prefix “un-” is accompanied by a hyphen to connect it to the word “American.”)

5. Join a Number to a Word

DESCRIPTION
Hyphens are used when joining a number to a word, especially when that number is written in numerical form.

APPLICATION
To use a hyphen to join a number to a word, put a hyphen between the number and the word that you are joining it to.

EXAMPLE

Rachel had a piece of 100-foot rope on her list for party supplies.
(In this sentence, a hyphen connects the number 100 to the word “foot.”)

6. Join a Prefix to a Date

DESCRIPTION
A prefix is a word, letter, or series of letters that is placed in front of other words or letters that change the meaning of a word. Prefixes can also add clarity to dates.

APPLICATION
To use a hyphen to join a prefix to a date, put a hyphen between the end of the prefix and the beginning of the date.

EXAMPLE

Velvet was all the rage when it came to women’s fashion in the mid-1920s.
(In this sentence, the date is clarified with a prefix, which is added with a hyphen between the prefix and the date.)

7. Separate Prefixes and Suffixes with Same Three Letters in a Row

DESCRIPTION
Sometimes compound words have three of the same letters that come in a row. When three letters come in a row, then it is time to use a hyphen to separate them.

APPLICATION
To use a hyphen to separate prefixes and suffixes with three letters in a row, put a hyphen in between the word and the prefix or suffix that starts with the same letter.

EXAMPLE

Patty’s laugh has a bell-like quality to it.
(In this sentence, the word “bell-like” has the letter “L” three times in a row, so a hyphen is used to separate them.)