A Word, Please: Can’t we all cooperate on whether to hyphenate ‘co’ as a prefix?

Sometimes I think the people behind punctuation rules are co-conspirators in a plot to drive us insane. Then I realize they could be coconspirators. That’s when I know their plot has succeeded.

Of all the prefixes in the English language, “co” may be hardest to hyphenate. The guidelines governing it are so inconsistent — varying not just from publisher to publisher but from term to term — that it seems no one knows how to hyphenate even simple everyday terms like “co-worker” / “coworker.”

Try to draw clues from your reading and you’ll end up even more confused. You could be looking at a top national news source one day and see “co-worker,” then five minutes later see it as “coworker” in a book or even a different news outlet.

Hyphenation rules are different for prefixes than for temporary compound modifiers, which are terms made up of two or more complete words to create a combination not found in the dictionary. Whenever you combine two whole words to form a new term, most publishing rule books say to join them with a hyphen, assuming the hyphen makes the term easier to read.

A spider-eating lizard is an example. Here, “spider” and “eating” are working together to form an adjective to modify the noun. “Spider-eating” isn’t in the dictionary. If it were, you wouldn’t have to worry how to hyphenate it. But because it’s not, you follow the rule that says you hyphenate these do-it-yourself compounds any time the hyphen aids comprehension.

These rules apply only to compounds you assemble yourself. If your term is already in the dictionary, just write it accordingly: good-looking, well-adjusted, man-eater.

Prefixes and suffixes are different. They have their own hyphenation rules that, extremely overgeneralized, go like this: Never hyphenate a prefix unless it looks weird unhyphenated. So “unsweet” would take no hyphen, but “un-American” would because the alternative, unAmerican, is clearly wrong.

More specifically, the rules say to hyphenate prefixes attached to proper nouns (anti-Elvis), numbers (pre-1970), words that, when combined with the prefix, would put too many of the same letter in a row (bill-less) and words that could be mistaken for other words without a hyphen (re-create).

But those are just general rules for hyphenating prefixes. Many prefixes have more exceptions than anyone can keep track of — or agree on.

For example, Associated Press style says that when “pro-” is used to indicate support for something, it should be hyphenated: pro-labor, pro-business, pro-war. But Chicago style, which most book publishers follow, says it should not be hyphenated unless the hyphen is necessary for readability. Of course, the style guide leaves that last part kind of murky, adding that “pro-life” needs a hyphen while implying through omission that “prolabor,” “probusiness” and “prowar” do not.

And by the way, never trust spell-checker when it comes to words created with prefixes and suffixes. A never-before-seen word created by attaching a legitimate prefix or suffix to another word is itself legitimate, despite spell-checker’s objections.

To me, “co” is the worst prefix. AP says it should be hyphenated any time it deals with someone’s occupation or position: co-author, co-chairman, co-sponsor, co-worker. Chicago style says that “co” should usually not be hyphenated: coauthor, cochairman, cosponsor, coworker. But, again, while affording the writer elbow room that, in some ways, just confuses things more.

Personally, I think “costar” looks like it should rhyme with “foster,” and “coworker” makes me think of someone who irks cows. So I lean toward hyphenating “co” whenever the alternative is too ugly.

But I look forward to the day that style guides learn to cooperate.

JUNE CASAGRANDE is the author of “The Best Punctuation Book, Period.” She can be reached at JuneTCN@aol.com.