It came up in conversation the other day about an argument one of my colleagues had with one of our Communications managers over the difference (or similarity, as she argued) between bi- and semi-. The context was some sort of miscellaneous report that needed to be put out twice a year. My colleague argued that “biannual” meant every two years, and the Communications manager argued that “biannual” meant twice per year, the same as “semiannual”. Apparently the discussion was quite heated, and my colleague, being in Finance, deferred to the vast knowledge of our Communications Department (keeping in mind these are the same people who have introduced CP to our organization and have thus added a sticky layer of ambiguity to all corporate copy).
I agreed with my colleague: biannual meant every two years, and semiannual meant twice per year.
Yet I felt compelled to check, as I tend to when confronted with some information that may prove my grammatical instinct wrong. I came across the following site: Grammarbook.com, and the following exchange, which I wanted to share with you. The strong emotions expressed by these commentators are not unlike my feelings on the Oxford comma and capitalization; I can appreciate having a violent reaction to grammatical abuse.
This quandry also suggests that given that bi- and semi- are often confused, it might be best to avoid these two prefixes (in this context), be less ambiguous, and specify to what you are referring (twice per year or every two years, etc…).
In the meanwhile, enjoy: