Manuscript Preparation, Copyediting, and Proofreading

Q. In 2.54 (CMOS 17) you recommend Webster’s Third New International Dictionary and call the Collegiate its “abridgment.” However, they sometimes disagree, which one wouldn’t expect from a true abridgment. (An example is “fire fighter” and “firefighter.”) Does the Third New International always trump the Collegiate when both contain the same word but with different spellings?

A. In fact, the Collegiate is more up-to-date than the Third. But the free dictionary at Merriam-Webster.com is more up-to-date than the Collegiate (on which it was originally based). And Merriam-Webster Unabridged (online only) is more up to date than the Third (which it succeeds). In some cases, this matters. But in vetting an issue like the spelling of a compound, where the goal is consistency rather than “correctness,” the right dictionary to use can simply be the one that’s close at hand.