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Where to put hyphens

After reading a draft of something by a colleague, I asked her how she decides when to use hyphens. She responded tartly: “Hyphens. You mean like in well-spoken, or half-assed? I’m not sure. I don’t care for them.”

Personally, I’m a big fan of hyphens and sarcasm won’t deter me.

Hyphens are different of course from dashes, which come in two flavors: en dashes and em dashes. The en dash (sometimes called the en rule) is the width of the letter n—longer than a hyphen but shorter than an em dash. The en dash is used to indicate ranges of numbers and to substitute for words like to or and (as in an east–west route). It’s also used many forms of joint action, such as a USCanada negotiation or the mind–body problem.

The em dash is the width of a letter m. It is used like parentheses or colons—to indicate an interruption, afterthought or elaboration—but while the parentheses are a soft whisper to the reader, the em dash is a hand waving for attention.

The em dash can even be doubled to indicate a sentence-ending ellipsis or the omission of letters. We often see this in dialogue such as “I think he had better——,” where the double em dash indicated that the sentence is never finished or in written examples like “I refer now to the testimony of Mr. F——.”

Hyphens are different than dashes. Hyphens indicate that words should be read as a unit, and they are about avoiding ambiguity among a series of words. Typically this involves phrases where a compound adjective modifies a following noun.

A small-business owner

A popular-movie critic

A second-language teacher

The hyphen is sometimes necessary to prevent momentary misreading (as in the above examples) but the grammatical convention of hyphenating compounds before nouns holds more generally, even when confusion is unlikely:

A Pulitzer-Prize winner

High-school graduates

A well-known actor

A two-thirds majority

A messed-up situation

When the compounds follow the verb, hyphens are usually omitted:

She won a Pulitzer Prize.

They all graduated from high school. The actor is well known.

I lost two thirds of my savings.

The situation is messed up.

There are of course various intricacies. (What would grammar be without them?) Thus, compound adverbs ending in –ly lack hyphens when they occur before an adjective plus a following noun. So we write that something is a completely obvious point, not a completely-obvious point.

Hyphens are necessary when adding prefixes to certain words that might otherwise be misread. I once received a post-it note on corrected reimbursement form telling me to “Please resign.” Words like re-sign, re-press, re-creation, and co-worker, call out for hyphens, as do words with identical vowels bumping up against each other like co-op or re-educate. Some prefixes, like the ones in pre-concert, anti-war, and self-worth, all-inclusive, and trans-national (among others), consistently require hyphens.

Hyphens are also important to use in many compound words, like mother-in-law, cat-of-nine-tails, five-year-old, and north-by-northwest.  And number words are hyphenated from twenty-one though ninety-nine.

Newly formed compounds tend to be written first as separate words or with hyphens and gradually become unhyphenated as they find their place in our linguistic consciousness. This makes hyphens especially fascinating to linguists and historians of the language.

Sometimes, however, compound words that were once hyphenated become so familiar that we treat them as single words, like the word online. Newly formed compounds tend to be written first as separate words or with hyphens and gradually become unhyphenated as they find their place in our linguistic consciousness. This makes hyphens especially fascinating to linguists and historians of the language. Thus, the formerly hyphenated compounds bumblebee, lowlife, and crybaby are now spelled as single words. And oddly, some once-hyphenated words even go the other way, being spelled with a space like ice cream and test tube. Seeing what still gets a hyphen and what no longer does lets us watch language change in process.

And because language changes, memorizing all the special cases and exceptions would be crazy-making. But if you focus on just a few principles like the ones mentioned here, your hyphens will usually be in the right place.

And take heart. Hyphenation has gotten easier, since most of us no longer need to worry about hyphenating words at the end of line of typed text (though those working in column inches still do). Yet it is oh-so-easy to get confused. Around my university, I’ve been seeing signs encouraging people to eschew cologne and other scents. They read:


Help us keep the air we share healthy and fragrance-free. Please DO NOT wear perfume, cologne, aftershave and other fragrances.

That should be FRAGRANCE-FREE ZONE and Help us keep the air we share healthy and fragrance free.

I resisted the urge to edit the signs. I wouldn’t want to be considered an anal-retentive English professor.

Featured image credit: “Chocolate ice cream and Rhubarb-rose ice cream” by Rebecca Siegel. CC BY-SA 2.0 via Flickr.

Recent Comments

  1. John Egan

    This kind of stuff actually drives me crazy ..even though I am in my own right a grammar-Nazi. However, until I had started using the free version of Grammarly I really had never paid much attention to the use of hyphens.. Grammarly called me out several times a day for lack of them. Now I pay attention. it’s still a silly thing to do.

  2. Donald F Smith

    I still believe that hyphens are required to keep prepositions from dangling.

  3. CMBG

    I disagree with one point: I would not hyphenate “Pulitzer-Prize winner.” Pulitzer Prize is a proper noun, like Fort Wayne or Ann Arbor or San Diego or Rolling Stones. You don’t write “a San-Diego resident” or “a Rolling-Stones fan.” The uppercase letters make clear which words are a unit.

  4. Fitz Townsend

    Throw them away! Use only when sense requires!

  5. Anushtup Haldar

    ‘A Pulitzer-Prize winner’ — hyphen should not be used here because ‘Pulitzer Prize’ is a single term and it cannot be divided up by a hyphen. A hyphen should be used in this case though — ‘He is a Pulitzer Prize-winning writer’.

  6. Anushtup Haldar

    Another comment: In ‘Help us keep the air we share healthy and fragrance free’, ‘fragrance free’ sounds rather odd; it should preferably be ‘fragrance-free’. If you don’t want to use a hyphen, you can write, ‘Help us keep the air we share healthy and free of fragrances.’

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