Q. You wouldn’t write “lineeditor,” so why “copyeditor”? Please help before my head explodes!

A. We know our preference for copyeditor isn’t popular with everyone, but judging from other copy words, it’s not all that weird. In American English, copy tends to form closed compounds, as this snippet from the 2003 first printing of Merriam-Webster’s Collegiate Dictionary (11th ed.) shows:*

Part of a scanned page from the first printing of the 11th edition of Merriam-Webster's Collegiate Dictionary, showing the entries for "copybook" through "copywriter."

With the sole exception of copy editor, each of those terms is closed up: copybook; copyboy; copycat, copycatted, copycatting; copydesk; copyedit; copyhold; copyholder; copyreader, copyread; copyright, copyrightable; copywriter. (Copyist is also one word, but it’s not a compound.)

One of them—copyrightable—even has the same number of syllables as copy editor, stressed in the same pattern.

Merriam-Webster has since added one-word copyeditor as a less common variant for the noun and two-word copy edit as a second-listed equal variant for the verb. Our preference splits the difference, favoring consistency with other copy words over the common usage reflected in the dictionary entry.

As for line editor, those two consecutive e’s preclude a move toward one word (à la linebacker or lineman), though we’d hyphenate the -ing and -ed participles as preceding modifiers, as in “line-edited manuscripts.”

We hope our answer has reached you in time.

* Note that those dots in the dictionary entries are called division markers. Not to be confused with actual hyphens, they show where hyphens may be added to words that need to be broken at the end of a line of text.