A Word, Please: Should you use a hyphen? It often depends on the part of speech

Do you ever login to your email? Or do you log in? Either way, do you use your log-in? During the holiday season, do you use gift wrap to gift-wrap gifts? Do you use your pickup to pick up the kids as they hang out at their favorite hangout?

If you find these matters intimidating, don’t. Even people with excellent language and punctuation skills can be stumped when it’s time to decide whether a term should be one word, two words or hyphenated.

Really, how could you guess that a water-skier water skis on water skis? And even if you did suss out that water-skiing takes a hyphen, your sussing skills would betray you if you had to write about skeet shooting, which is not hyphenated.

If you don’t want to stress over these matters, good news: You don’t have to. No one is expected to know them all. Not even copy editors commit all these terms to memory.

But if you would like to approach these hyphenation situations with greater confidence, you need to know where to look them up and how.

Most of the time, you’ll find answers in the dictionary. But don’t just skim the entry word to see if there’s a hyphen in it. Note what part of speech you’re looking for — noun, verb or adjective — then find that form under the entry word. Otherwise, you could glimpse “water ski” in the dictionary and assume it’s correct to write that you like to water ski.

According to Merriam-Webster’s, the noun meaning a piece of sports equipment takes no hyphen — it’s a water ski. But the verb does — you water-ski. Water-skier has its own entry, complete with hyphen.

Of course, water-skiing probably doesn’t come up as much as logging in to websites and email accounts. But the terms “log in” and “log on” are a little messier. For a simple guide, remember that the verb form is two words. You never login to your account. You log in. Merriam-Webster’s actually doesn’t have an entry for “log in” or “login.” They have one for “log on,” where they note that “log in” is an alternative form.

Interestingly, there is no noun form of “logon” or “login” in Merriam’s. Instead, the dictionary lists the noun as hyphenated. So according to this dictionary you log on using your log-on and you log in using your log-in.

Personally, I think Merriam’s is a little behind the times on this one. It’s common for two-word and hyphenated forms to slowly merge into closed one-word forms, like “teen-ager” and “good-bye.” So I’ll allow “login” or “logon” as a noun when I’m editing.

I will not, however, allow “log into” or “log onto.” To my mind, “log in” and “log on” are phrasal verbs and “log into” and “log onto” are not. Merriam’s has my back on this to a certain degree: The dictionary treats “log in to” and “log on to” as the preferred forms, but it also recognizes “into.”

In most cases, you’ll find that verb forms tend to be open compounds: pick up, gift wrap, hang out. Nouns are often one word: hangout, pickup. But you’ll find a lot of nouns hyphenated in the dictionary, too: problem-solving, decision-maker. Some nouns aren’t listed, like the paper we call gift wrap. In those cases, you can just combine two words, usually without a hyphen: gift wrap.

Adjectives are a little different. For these, if they’re not in the dictionary, there’s a rule you can apply: Hyphenate any two words used to modify a noun anytime the hyphen could aid understanding. A woman eating lobster, after all, is quite different from a woman-eating lobster. But if your compound includes an adverb that ends in “ly,” no need for a hyphen. The adverb form itself eliminates all chance of confusion when you write about a “happily married couple” or a “beautifully composed musical score.”

Just don’t feel bad that you don’t know all the answers. No one does.

June Casagrande is the author of “The Joy of Syntax: A Simple Guide to All the Grammar You Know You Should Know.” She can be reached at [email protected].

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