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Use of Hyphens

Published by at August 17th, 2021 , Revised On December 12, 2022

To understand how to use hyphens, first, you must learn what hyphens are. A hyphen ( – ) is a punctuation mark used as a joiner. It is used to join two parts of a single word. Although you may see hyphens appear after some of the prefixes, the main role is to link compound words.

You can use the hyphen to:

  • link compound nouns (e.g., mother-in-law, runner-up, great-grandmother)
  • link compound adjectives (e.g., “air-tight” seal, “narrow-minded” man, “old-fashioned” lady)
  • link prefix to a word (e.g., re-write, re-examine, ex-wife)

A hyphen shows that the joined word is a single entity. It aims to eradicate obscurity.

Compound Nouns

A single noun made up of two words is called a compound noun.

Compound nouns are made by joining nouns with phrasal verbs or adjectives. They do not always require a hyphen, but when they are made by joining phrasal verbs, you either use a hyphen or combine them into a single word. For example

Phrasal verbs Phrasal Verbs used as nouns
I saw him trying to sneak in last night He sneaked-in last night
Professor told him to go ahead with the reading He received a go-ahead from the professor

Compound Adjectives

Like compound nouns, a compound adjective consists of two words working together to modify a noun. A compound adjective requires a hyphen when it is used before a noun. For example;

Compound Adjectives Compound adjectives used before nouns
He is two years old. She adopted a two-year-old boy.
The table has four feet. It is a four-feet long table.
The monster had green eyes. It was the green-eyed monster.

However, If the compound adjective comes after a noun, you do not need to use a hyphen.

Compound adjectives before a noun Compound adjective after a noun
Well-known politician. The politician is well known.
Brightly-lit room The room was lit brightly.


A compound adjective that ends with “ly” does not need a hyphen as well. For example, “The Company’s highly skilled labor is responsible for smartly paced work.


Prefixes are added before a word to change its meaning, such as “im-possible,” “un-able.”A set of instructions does not exist, which guides whether we should use a hyphen to link prefix to a word or not. If you are “unsure” about using a hyphen, check the dictionary for correct information. But generally, if a prefix is used before a capital letter or a number, always use a hyphen.

Hyphenated prefixes Unhyphenated prefixes
Anti-Muslim Anticrime
Inter-Bank interlinked
Pre-18th century Predated

Hyphens usually are not used if a term becomes too familiar. For example, e-mail has now turned into the email.

Using Hyphens

A hyphen can transform the meaning of a sentence, so be careful while using it. Sometimes an unnecessary use of a hyphen can make your sentence unclear and confusing for the readers. For example;

Words Transforming it using the hyphen Meaning
2 year old boys
  • 2-year-old boys
  • 2 year-old boys
  • Boys who are two tears old
  • 2 boys who are one year old
Long standing
  • Long-standing
  • Long standing
  • Something which has existed for a long period of time
  • Standing for a long time

Extra Guidance

Even if you are an experienced writer, hyphens can confuse you. One thing to make your writing better is consistency. Be consistent in hyphenating terms. If you write ”un-expected” make sure to use a hyphen for prefixes like “un-sure,” “un-aware,” “un-ambiguous.” Always consult the dictionary to be sure of whether you should use a hyphen or not, and be careful about overdoing it. A hyphen should only be used if it is genuinely needed.

A hyphen is used:

  • To join the words of a compound adjective
  • To join the words of a compound noun
  • To join a prefix to a word
  • In compound adjectives to show they are single entities.
  • In compound nouns to show they are single entities.
  • With prefixes.

Using hyphens to link multi-word but single entities makes your text easier to read, and it showcases your writing skills.

About Alvin Nicolas

Avatar for Alvin NicolasNicolas has a master's degree in literature and a PhD degree in statistics. He is a content manager at ResearchProspect. He loves to write, cook and run. Nicolas is passionate about helping students at all levels.