Abbreviations

Q. Do you recommend the use of BCE (Before the Common Era) and CE (Common Era) instead of BC and AD? Has the debate about these been settled or is it still in flux?

Q. We want to know the usage of “etc.” at the END of a sentence, that is, as the last word of a sentence. Is it spelled out?

Q. How should we handle file extensions like PDF (portable document format, an Adobe Acrobat file)—lowercase, preceded by a period, or all uppercase? Other examples are GIF and JPG (or JPEG).

Q. I hope you can resolve a dispute between me and my editor. After introducing an acronym, e.g., “Bureau of Land Management,” to “BLM,” I like to drop the “the” in introducing it. For example, I think the least awkward way is to say “BLM is charged with the oversight of . . .” as opposed to “The BLM is . . .” Do you have any rule that covers this issue?

Q. I am trying to find out when you write if you say “an MBA” or “a MBA.” Here is the example I’m trying to figure out: He earned an MBA from Harvard Business School and a BS from the Wharton School, University of Pennsylvania.

Q. I am a graduate of the U of C and working in an environment surrounded by colleagues with Oxon and Cantab after their degrees (Oxon and Cantab being abbreviations for the Latinized forms for Oxford and Cambridge; see section 10.43 of CMOS 16). Here is my stupid question: Is there a Latinized form for “Chicago” that I could use similarly? Although the word Chicago is certainly not of Indo-European origin, that certainly would not deter someone from its Latinization.

Q. More often in bibliographic citations, I am seeing the abbreviations s.l. and s.n. in place of n.p. where the place and/or publisher are unknown. What do these abbreviations mean, and are they likely to take over n.p.?

Q. We have a new employee who holds two PhDs. She insists on having her name listed as “Jane Doe, PhD, PhD.” We are in a university environment and agree that degrees are important, but doesn’t this seem a bit much?

Q. I work for a technical magazine. I’ve always been taught that when it comes to acronyms, the rule is you spell out the words first followed by the acronym in parentheses, and then use the acronym for later references in the copy. If there are no other mentions of the acronym later in the copy, then you just spell it out without the acronym in parentheses. Is this correct? My coworker is debating this with me. Thanks!!!!!!!

Q. Dear Sir or Madam: My client prefers to use the article a before an abbreviation such as LCMOS. I suggest using an, since the letter L is pronounced “ell.” What does the Chicago Manual of Style recommend?