Hyphen or dash: What’s the difference, and when to use which?

Here’s a punctuation “issue” that people have asked me about lately: what’s the difference between a hyphen and a dash, and when do you use which?

Difference #1 — a hyphen is short, and a dash is long.  In Morse code, hyphens would be like the “dots” while dashes would be like, well, the “dashes.”

Difference #2 – a hyphen pulls things together, but a dash pushes them apart.

In the olden days of typewriters, if you had to split up a word at the end of a line, you “hyphenated” it (at a syllable break only!) to “pull” the word together from the end of one line to the beginning of the next.

A line might look some-

thing like this

Hyphens are used to create adjectives from two words:

An old-fashioned ice-cream social

A well-deserved honor

A time-sensitive document

Hyphens also pull together compound nouns before they become commonly accepted as one word.  For example, the noun “make-up” is now usually spelled “makeup.”

(Disclaimer: make sure you’re using “makeup” as a noun, as in cosmetics, if you leave out the hyphen.  If you use it as verb, it’ll be two words: I have to “make up” a test.  If it’s an adjective, it’ll be hyphenated: I have to take a “make-up” test after school.)

For a long time electronic mail was referred to as E-mail or e-mail; now I most commonly see it as “email.”  So if you can remember this progression from 1) two separate words to 2) a hyphenated word to 3) one single, new word, then it may be easier to remember what a hyphen does: it pulls things together.

Dashes, however, push things apart.  There are two kinds of dashes (who knew?), one short and one long.  The shorter dash is called an en dash; the longer is called an em dash.  They are named for the letters “n” and “m.”  An “n” is shorter (one hump) than an “m” (two humps).

Here’s a handy visual to show the differences in length:

Hyphen vs dash

The en dash is used either to show a range of numbers or to indicate a relationship pair; it replaces the word “to” or “and”:

Do the problems on pages 61–70 for homework.

World War II (1940–1945) truly spanned the globe, with battles fought on several continents and at least two oceans.

The Army–Navy game is always must-see viewing in our house.

That last sentence used both an en dash (to indicate the pair of rivals) and a hyphen to create the adjective that describes what kind of viewing (must-see) occurs.  Often you might see a hyphen incorrectly used to punctuate the Army–Navy game.  But Army and Navy aren’t two terms getting pulled together to create one whole new concept, as in American-style football.  Army and Navy are the two rival teams competing in this event; they are distinct from each other, so they need the dash to maintain their separation/distance.  It’s the Army and Navy game, like the current Presidential administration is the Obama–Biden (Obama and Biden) administration.

Em dashes are used to forcibly separate ideas within a sentence—like this.  I could have used a comma to accomplish the separation, like this.  But using a dash calls attention to the words “like this.”  Like commas or parentheses, em dashes used in the middle of a sentence come in pairs:

Using dashes in the middle of a sentence—like this—provides a much stronger break (and, thus, emphasis) than using commas.

Sometimes it’s a nice stylistic twist to open a sentence with a list, and then use a dash to close the list and follow it with the thing that all of the listed items constitute:

Wife, mother, confidante, assassin—Mary juggled many roles in her life.

(Where did that come from?  Too many thrillers and mystery novels, I guess.)

Here’s how to make en and em dashes in Microsoft Word.  Probably there are more elegant ways than this, but I haven’t found them.

To make an en dash: After typing the last character before the en dash, type a space by hitting the space bar.  Then type a hyphen.  Type another space.  Then type your next numeral or word.  Type another space.  As soon as you hit the space bar following the second numeral or word, the hyphen you typed will turn into an en dash.

To make an em dash: After typing the last word or character before the em dash, immediately type two hyphens, right next to each other in a row.  Don’t type a space before those hyphens, as you would if you wanted to make an en dash.  After typing your two hyphens, immediately type your next word.  Then type a space.  As soon as you type the space after the word that followed your two hyphens, the two hyphens will turn into an em dash.

(Update: As soon as I published this post, I realized that the more “elegant” way to make en and em dashes would probably be to “insert” them as symbols.  I had never thought of doing that before, duh.  So I checked, and sure enough found ’em!)

So I think that about does it for hyphens and dashes.  Hope this is helpful 🙂

About Katherine Wikoff

I am a college professor at Milwaukee School of Engineering, where I teach literature, film studies, political science, and communication. My blog is a space for playing with ideas about creativity, innovation, lifelong learning, and the nature of "insight."
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6 Responses to Hyphen or dash: What’s the difference, and when to use which?

  1. Jessica Slavin says:

    “Wife, mother, confidante, assassin—Mary juggled many roles in her life.” Ah, thanks for bringing a chuckle to my morning! 🙂

    Like

  2. As usual Katie you hit the ball out of the park. Maybe you can help clarify affect and effect sometime. I’d like to get rid of the word impacted, which I associate with teeth, and interface which I associate with sewing. I guess I’m too old-fashioned for words. Do people even sew anymore??

    Like

  3. I always wondered why/how Word was “helping” me!! Now I know!!

    Like

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