• 3-minute read
• 21st January 2021

Writing Tips: When to Use a Hyphen with the Prefix “Ex”

“Ex” is a common prefix in English. But how you punctuate this prefix may depend on how you use it. So, when do you need a hyphen between “ex” and the word following it? Check out our guide to make sure your writing is always error free.

Ex (Out of or From)

“Ex” appears without a hyphen at the start of many English words. This comes from a Latin word meaning “out of” or “from.” We still see this in several modern words:

To exit a building means to go out of it.

To exclude someone means to shut them out.

If something is exterior, it is outside.

This origin is less obvious for other words, such as “experience” or “explain.” But if we look at where these words come from, there is usually a connection. “Experience,” for instance, essentially means “try out.” And the word “explain” can be broken down into parts meaning “flatten out,” giving it its sense of “make plain.”

The key thing to remember is that none of these words are hyphenated. In fact, there is only one use of “ex” that does require a hyphen, as we will see next.

Ex- (Former)

More recently, “ex” has entered use with a hyphen as a prefix meaning “former”:

She is his ex-girlfriend. They split up years ago.

The ex-president was in office from 1980 to 1984.

He is the ex-manager of Liverpool Football Club.

In any case like this, you will need a hyphen between “ex” and the main word.

The key exception to this rule is if you are using the word “ex” on its own. In this case, it is an informal term used to refer to a former romantic partner. For example:

I saw my ex the other day, but we didn’t speak.

I’m good friends with my exes.

Since this is a standalone word rather than a prefix, it does not need a hyphen.

Summary: When to Use a Hyphen with “Ex”

The prefix “ex” appears at the start of many English words. However, the correct punctuation for a word will depend on how you are using this prefix:

• When using “ex” to mean “former,” add a hyphen (e.g., ex-boyfriend).
  
• In all other cases, do not add a hyphen after “ex” (e.g., exit, explode, explain).

If you need any more help with your writing, though, our proofreaders are here to help. You can even upload a trial document and try our services for free today.