Bimonthly vs. semimonthly


Dear Conan,

Does bimonthly mean twice in 1 month, or every other month?? And what is the other one called?



Oh, Carolyn,

You’ve stumbled onto one of those prickly questions that has plagued mankind for centuries (actually, about a century and a half). Guess what? According to Merriam-Webster, it means either! How annoying is that? However, bimonthly has consistently been used in publishing (thus saith, and they’re, like, some of the dudes who invented English) to mean every two months. If it helps, semimonthly always means twice a month.

My advice? Stick to the concise, unambiguous terms “twice monthly” and “every other month.”

Your ally in correctness,