Q. Hi, can you tell me what “pl.” stands for in “vol. 5 (1822), pl. 57”? Thanks!
A. It most likely stands for “plate”—as in an illustration printed on special paper and bound together in a separate section known as a gallery; these pages typically aren’t paginated with the rest of the book, so plate or figure numbers must be used instead of page numbers to refer to individual pages in the gallery. CMOS 10.42 includes nearly 250 abbreviations that might appear in scholarly publications, including “pl.” As you will see in that list, the abbreviation “pl.” can mean either “plate” or “plural” but is best avoided for the former. Whoever recorded “pl.” in the example you cite apparently didn’t see our list.
Q. I’m wondering about omitting the periods for US Department of Energy. On its site, it’s U.S. Do we follow the department’s preference or Chicago style?
A. The name of the organization is the United States Department of Energy. When you follow Chicago style to write “US Department of Energy,” you are abbreviating the fuller form of the name. The abbreviation at Energy.gov probably follows the GPO Style Manual, published by the US Government Publishing Office. GPO style uses periods in “U.S.” (and “U.K.” and the like), and those periods are a matter of government style. But unless you’re writing for the government, it is safe to omit them.
Q. What is the proper way to write Dr. Tom Smith Jr., M.D.?
A. Use MD or Dr., but not both. Please see CMOS 10.16 and 10.19. Some style guides use periods in M.D. and put a comma before Jr., but Chicago prefers the following forms:
Tom Smith Jr., MD
Dr. Tom Smith Jr.
Q. Will you provide examples of what is considered “humanistic” versus “scientific or statistical” when addressing the use of the symbol % or the word percent?
A. In academe, the humanities include subjects like modern and classical languages, geography, linguistics, literature, history, law, philosophy, archaeology, religion, ethics, history, and criticism. Science and statistical fields include mathematics, engineering, statistics, computer science, biology, chemistry, accounting, medicine, and sociology. There are no strict lines. General writing in a technical field (such as a feature on astrophysics written for a popular magazine) might feature a nontechnical writing style. Any content that includes a lot of numbers and percentages is a good candidate for using the % symbol instead of writing percent over and over.
Q. I just read your explanation of the use of Ms with a period as a shortened combination of Miss and Mrs. Boy are you wrong. Please read the feminist history and arguments of the early 1970s.
A. This use of Ms. predates the 1970s by several decades. Please read your dictionary!
Q. Hello. A term you used in your hyphenation table is slightly incorrect, I believe. You call the units of measurement (m, kg, ft.) “abbreviations.” (I assume that things like MB and GHz also fall into this category?) According to Merriam-Webster, an abbreviation is “a shortened form of a written word or phrase used in place of the whole word or phrase. ‘Amt’ is an abbreviation for ‘amount.’ ‘USA’ is an abbreviation of ‘United States of America.’” That has nothing to do with the examples in the table.
A. You are right. However, in CMOS the umbrella term abbreviation is used for acronyms, initialisms, and contractions, as well as for shortened (abbreviated) forms (ibid., vol., prof., etc.), except where greater specificity is required. This is stated more fully at 10.2. I’m sorry if it caused you confusion or inconvenience.
Q. Greetings! When using a slash in the abbreviation w/ should there be a space after it or not? E.g., Fluffy went down the street w/Cookie? or Smoochie went to the store w/ Pookie?
A. Add a space. W/ is an abbreviated word, not a prefix. Of course, you would never use w/ in regular, formal writing. It’s more for laundry lists, emails to friends, texts, and so forth.
Q. I’m proofreading a manuscript in which US is abbreviated without periods throughout. But when it’s part of a compound, periods are added. (“The U.S.-ratified agreement,” or “U.S.-friendly leaders,” for example.) My impulse is to change it, but it appears so regularly that it seems to have been done this way on purpose. (There are 35 instances over 400 pages of text.) Is there ever a reason to use periods in some instances but not others, when you’re abbreviating “United States”?
A. We shy away from the use of never, but this seems weird and definitely worth querying. Perhaps it’s the result of a poorly executed global search-and-replace move that changed all mentions except these (or vice versa). If you can’t query, edit them with a note that you did so. It shouldn’t be too hard to put them all back the way they were if there turns out to be a good reason for the inconsistency.
Q. I frequently use the acronym GAAP, which stands for generally accepted accounting principles. Would the acronym be considered a collective noun? Would I treat GAAP as a singular subject when using the acronym but as a plural subject when spelling it out? What if I do both (spell it out and then put the acronym in parentheses)?
A. Browsing online reveals that the initialism GAAP is treated as a singular, and the spelled-out version is treated as a plural, but as you sense, that’s awkward. The most thoughtful and professional solution I saw was to avoid ever using the acronym as the subject of a sentence. Instead, the writers used it either as an adjective (GAAP pronouncements, GAAP terminology, GAAP model) or as an object (according to GAAP, who came up with GAAP, history of GAAP). That seems like a good plan.
Q. When, if ever, is it acceptable to use the abbreviation for To Whom It May Concern (TWIMC) in a letter?
A. As a form of address? Let’s say never.