Hyphens, En Dashes, Em Dashes

Q. I’m copyediting a novel in which the author has gone hyphen-mad. She is fond of such terms as “horse-yard,” “juniper-wood,” “yard-gate,” “cedar-grove,” and so on. I want to defer to an author’s stylistic preferences, but I feel too much is too much. In most cases, the meaning seems perfectly clear without a hyphen. What can I say to this author?

A. Are you working for a publisher? If so, they will have guidelines that you can wave at the author. (Here, we follow Merriam-Webster.) If not, you should let her know what source you follow for hyphenated compounds and ask if she has any objections. If you need to justify your method to the author, try to find cases where she’s inconsistent and explain that in order to arbitrate, you’ll be using a dictionary. Most authors are in favor of consistency, and will understand that following a reference book is the best guarantee of this. Point out that an abundance of hyphens can give a jittery feel to a narration. (A fiction writer will fear that.) Finally, make sure she understands that the same phrase can appear with and without a hyphen depending on its use as a noun or adjective, and that you’ll be marking them accordingly.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]