We’ve spent the first few weeks of the new year sweating the small stuff?abbreviations, initialisms, and other short forms. We’ve looked at Canadian usage and examined when to use capital letters and periods. This week we’ll wrap up our quick survey on short forms and sort out some more basics: plurals, possessives, and more.
Most of the time?when you have an abbreviation in all caps with no periods in between?form the plural by adding an s. That’s right, no apostrophe.
Example A: We’ve spoken to three MPs about the issue.
Example B: I counted four CEOs in the room.
The general rule also applies when you have an abbreviation that’s become almost unrecognizable as anything other than an ordinary word (caps or not):
Example C: The machine’s lasers cut the steel.
Not surprisingly, there are a few exceptions to the rule. First, for abbreviations that use multiple periods, form the plural with apostrophe + s; this avoids any ambiguity over the purpose of the s.
Example D: I was so jet lagged that I had trouble sorting out my a.m.’s and p.m.’s.
Second, use apostrophe + s when you have single-capital abbreviations:
Example E: The professor’s Q&A session was mostly Q’s and offered very little in the way of A’s.
The rule for possessives is simpler than you might expect: form possessives of abbreviations just like you would possessives of other nouns. For abbreviations not ending in s, add apostrophe + s:
Example F: The BMW’s fender was damaged in the collision.
Example G: The OED’s latest edition lists a variant spelling.
For abbreviations ending in s, follow the rule dictated by whatever style guide you’re using.
To determine which indefinite article (a or an) to use with an abbreviation, use the read-aloud test: if the first sound reads like a vowel sound, use an just like you would for a word starting with a vowel. Otherwise, use a.
Example F: Sarah briefly dated an NFL player.
Example G: Sarah dumped the NFL player and started going out with a NASA scientist.
A caution: some abbreviations are read aloud as the full noun they’re abbreviating?like “MS” for “mansuscript.” In that case, use the indefinite article that goes with the noun:
Example H: I received a MS from an Australian writer the other day.
Abbreviation punctuation and usage spans dozens of categories and special rules?but a knowledge of the basics will get you started and provide you with a springboard to use should you need to explore further. Memorize the general rules and the most common exceptions, and you’ll find you can navigate the world of acronyms and initialisms with ease.
Christina M. Frey is a book editor, literary coach, and lover of great writing. For more tips and techniques for your toolbox, follow her on Twitter (@turntopage2) or visit her blog.