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Hyphens, En Dashes, Em Dashes
Q. Hi. I’m working on a label for an image in a printed brochure. The entire label is “bison shoulder blade hoe.” How would you punctuate that—with an en dash (“bison–shoulder blade hoe”)? Or hyphens (“bison-shoulder-blade hoe” or “bison shoulder-blade hoe”)? I was thinking that technically an en dash would be correct according to CMOS 6.80, but that seems too formal and, as CMOS states, unlikely to be noticed by most. There is no room to reword it. Thank you!
Q. Regarding open compounds, would an en dash be correct in “Mr. Potato Head–like head” and “rubbing alcohol–soaked cotton”? Thank you!
A. See CMOS 7.85: “With the exception of proper nouns (such as United States) and compounds formed by an adverb ending in ly plus an adjective (see 7.86), it is never incorrect to hyphenate adjectival compounds before a noun.” The goal of adding such hyphens is to clarify the meaning of the text.
To start with the bison, that example refers to a hoe fashioned from a bison’s shoulder blade. The three relevant terms are bison, shoulder blade, and hoe, so the clearest version is the last: “bison shoulder-blade hoe.”
We agree that an en dash wouldn’t work all that well; in “bison–shoulder blade hoe,” readers would need to recognize “shoulder blade” as a distinct compound before “hoe.” You’d be better off leaving the words open (“bison shoulder blade hoe”), trusting readers to sort out the modifiers without the help of hyphens or dashes. Or you could use two hyphens (“bison-shoulder-blade hoe”), but that doesn’t single out “shoulder blade” either, so the uncluttered open version is better.
As for the second question, it would be hard to improve on “Mr. Potato Head–like head,” where the en dash provides a perfect illustration of the principles covered in CMOS 6.80. And though the en dash is technically correct also in “rubbing alcohol–soaked cotton,” we’d advise rephrasing: “cotton soaked in rubbing alcohol.” Readers then won’t have to mentally sort out the string of modifiers to identify “rubbing alcohol,” a compound that, like “shoulder blade” in the bison example, lacks Mr. Potato Head’s prominent initial caps. Nor would “rubbing-alcohol soaked cotton” work; participles like “soaked” always require a hyphen in that position (see the hyphenation guide at CMOS 7.89, sec. 2, under “noun + participle”).