High Quality Product or High-Quality Product? When to Hyphenate Modifiers

It might sometimes seem like people just toss hyphens randomly into their writing. And with so many different rules and various situations when you do or don’t need a hyphen (even for the same word!), it’s very possible that some writers have given up and do exactly that.

However, you’ll be relieved to hear that this particular hyphen rule is pretty cut-and-dry. In fact, I can break down the rule about hyphenating compound modifiers into just four words: hyphenate before; don’t after.

What Is a Compound Modifier?

A compound modifier (also called a phrasal adjective) is two or more words that are working together to form a single adjective. It’s essentially a compound word that is working as an adjective.

Often, the compound modifier could function as a noun on its own, but when it’s functioning as an adjective instead, it’s a modifier. Here’s an example:

He got ready to ask the million-dollar question.

Million is its own word, and so is dollar. But in the example above, these words are working together as a single adjective to the noun question.

Note that compound modifiers are always multiple words working together to form a SINGLE adjective. If you have MULTIPLE distinct adjectives before a noun, separate those with commas rather than using hyphens:

I drove to school in a smelly, ugly car.

NOT

I drove to school in a smelly-ugly car.

In this case, the car is being described as both smelly AND ugly. They’re two separate, distinct adjectives, so they don’t make up a compound modifier.

The words in a compound modifier work together to form a single adjective, like this:

Renting the new apartment was the second-best decision I made that year.

“Second-best” is ONE adjective. The decision wasn’t both second AND best—just second-best.

So here’s the weird thing about compound modifiers: sometimes they ARE hyphenated (as in “million-dollar question”) and sometimes they’re NOT (as in “the question was worth a million dollars”). So what’s the deal with that?

The Rule: Hyphenate Before, Don’t After

The simple rule about whether or not you should hyphenate a compound modifier is this: hyphenate before, don’t after. When the compound modifier comes BEFORE the noun it’s modifying, you SHOULD hyphenate it. When it comes AFTER, leave the hyphen OUT.

I toured the third-floor apartment in New York City before I moved there.

Third-floor is modifying apartment. Because it comes BEFORE apartment, we DO need to hyphenate third-floor.

The apartment I toured in New York City was on the third floor.

Third floor is still describing the noun apartment, but because it comes AFTER apartment in the sentence, we can leave the hyphen out.

According to various style guides, this rule is all about clarity. Including too many modifying words before your noun can clog up your sentence and leave your reader wondering which words are functioning as nouns and which are functioning as adjectives.

Take, for example, the sentence above. If we left out the hyphen, the first part would read “I toured the third floor apartment.” The reader might pause after “third floor” and think we meant to say that we toured the entire third floor, not the third-floor apartment. To give a clear picture of how each word is functioning, a hyphenated compound modifier is essential.

Another way that hyphenated compound modifiers provide clarity is with this sentence:

She donated much-needed clothing to the shelter.

Without a hyphen there, it would say

She donated much needed clothing to the shelter.

In that case, we don’t know whether needed is paired with much or clothing (“much…needed clothing” or “much needed…clothing”? Did she donate a lot of needed clothing or did she donate clothing that was very much in high demand?). Adding a hyphen clarifies that she donated clothing that was in high demand.

Here’s another example like that:

I pulled on my light green gloves.

Are my gloves a light shade of green, or are my green gloves light rather than heavy? Adding a hyphen clarifies that they are a light shade of green:

I pulled on my light-green gloves.

If you’re talking about not-heavy gloves that are green, you don’t have a compound modifier: you have multiple modifiers that are each independently modifying the noun. In this situation, use a comma instead to separate those individual modifiers:

I pulled on my light, green gloves.

The Chicago Manual of Style lists these examples of compound modifiers that are hyphenated BEFORE but not AFTER the noun they modify:

• a five-year-old child BUT the child is five years old
• an emerald-green tie BUT the tie is emerald green
• a half-hour lesson BUT the lesson is a half hour
• a fifty-million-dollar deal BUT a deal worth fifty million dollars
• a hundred-meter race BUT the race was a hundred meters
• a seven-pound, eight-ounce baby BUT the baby weighed seven pounds and eight ounces
• a six-foot-two man BUT the man was six feet, two inches tall
• a third-floor apartment BUT the apartment was on the third floor
• the second-best decision BUT the decision was the second best
• the three-thirty train BUT the train arrived at three thirty
• a high-quality sample BUT the sample was high quality
• a middle-class neighborhood BUT the neighborhood was middle class
• a tight-lipped person BUT the person was tight lipped
• an open-ended question BUT the question was open ended.
• a much-needed addition BUT the addition was much needed
• a well-read child BUT the child was well read
• a mountain-climbing enthusiast BUT he loved mountain climbing
• dressed-up visitors BUT the visitors were dressed up
• over-the-counter drug BUT the drug was sold over the counter

The Exceptions to the Rule: Proper Nouns and Adverbs Ending in ly

This rule about always hyphenating compound modifiers before the noun and never after has two important exceptions: proper nouns and adverbs that end in -ly.

the President of the United States

OR

the United States President

NOT

the United-States President

Proper nouns are clearly paired with one another (almost no one would assume that we meant “the States President that was United” rather than “the President of the United States” in the above example), so hyphens are not needed for clarity there.

Similarly, the suffix -ly signals that the adverb it’s attached to is modifying the next word. It’s basically a hyphen in itself, connecting the adverb to the word that follows it.

the crowd was poorly dressed

OR

the poorly dressed crowd

NOT

the poorly-dressed crowd

Remember that this exception only applies when the adverb ends in -ly; if the adverb does NOT end in -ly, the hyphenation rule still applies.

the crowd was well dressed

OR

the well-dressed crowd

NOT

the well dressed crowd

According to The Chicago Manual of Style, proper nouns and -ly adverbs are the exceptions to the rule because “ambiguity is virtually impossible” in both instances.

Here are some more examples of these two exceptions:

Examples:

• a highly paid teacher NOT a highly-paid teacher
• a fully open can NOT a fully-open can
• a mildly amusing jokester NOT a mildly-amusing jokester
• the United States government NOT the United-States government
• the Adam Wilkinson memorial garden NOT the Adam-Wilkinson memorial garden
• African American president NOT African-American president
• North Central region NOT North-Central region
• Middle Eastern countries NOT Middle-Eastern countries

There’s one more exception to this hyphenation rule, but it’s much less common than the -ly adverbs or proper nouns. The exception is a noun + numeral/enumerator:

• a type A executive NOT a type-A executive
• type 2 diabetes NOT type-2 diabetes
• size 12 slacks NOT size-12 slacks
• a page 1 headline NOT a page-1 headline

When in Doubt…

Although there are a couple of exceptions to the hyphenated compound modifiers rule, nine times out of ten, the “hyphenate before the noun; don’t after” rule will be true. In fact, The Chicago Manual of Style says that, besides those few exceptions, “it is never incorrect to hyphenate adjectival compounds before a noun.” If you’ve ever read a grammar style guide, you know just how rare it is to see the word never in it, so this is a pretty reliable rule!

If you have any questions about hyphenated compound modifiers, leave them in the comments, and I’ll do my best to find an answer for you!

Sources:

• The Chicago Manual of Style. 17th ed. Chicago, IL: The University of Chicago Press, 2017.
• Ebbitt, D. R., and W. R. Ebbitt. Index to English. 8th ed. New York: Oxford University Press, 1990.