What Are Hyphens? (with Examples)A hyphen (-) is a punctuation mark used to join the separate parts of a compound word. A hyphen is a joiner.
A hyphen is used to join the words of a compound adjective (e.g., five-page document), to join the words of compound noun (e.g., cooking-oil), and to join a prefix to a word (e.g., re-examine).
One of the main functions of a hyphen is to show the joined words are a single entity (e.g., a single noun or a single adjective). A hyphen is also useful to eliminate ambiguity. For example, a hyphen makes it clear that cooking-oil is oil for cooking and not oil that is cooking.
Below is a quick overview of when hyphens are used. Click here for a more comprehensive version of this list or click on the "Read more" link with each entry.
When to Use Hyphens (A Very Quick Overview)Below is a quick overview on when to use hyphens.
(1) Use hyphens in compound adjectives to show they are single entities.
In the examples below, the compound adjectives are shaded.
- free-range eggs
- two-day break
- four-seater aircraft
Read more about hyphens in compound adjectives
Read more about alternatives to hyphens in compound adjectives
(2) Use hyphens in compound nouns to show they are single entities.
In the examples below, the compound nouns are shaded.
- Nitrous oxide, commonly known as laughing-gas, has a slightly sweet odour and taste.
- I have lost my water-bottle.
- He was seen by a passer-by.
- Did he marry his sister-in-law?
Read more about hyphens in compound nouns
Read more about forming the plurals of compound nouns
(3) Use hyphens with prefixes.
- cooperate and co-operate
- antifascist and anti-fascist
Read more about hyphens in prefixes
Much more about using hyphens What is punctuation? What are apostrophes? What are colons? What are commas? What are dashes? What is ellipsis? What are exclamation marks? What are hyphens?
What is a full stop / period? What are parentheses (i.e., brackets)? What are questions marks? What are quotation marks? What are semicolons? Glossary of grammatical terms