You might think that because all of these words begin with the prefix “bi” (meaning two) that the words would all just mean two of something. If so, you would be mistaken. Such is the logic (or lack thereof) when we are dealing with the English language.
The words “biweekly” and “bimonthly” each have two definitions.
- biweekly: twice a week
- biweekly: every two weeks
- bimonthly: twice a month
- bimonthly: every two months
Clearly, twice a week is much more frequent than every two weeks. As such, those who wish to use these words must take care to add further information to clarify the definition they intend to convey.
The word “biannual” has a very specific meaning.
- biannual: twice a year
This word is often confused with “biennial”, which means every two years. So, if you plan to meet in July and December of the same year, you will have biannual meetings. On the other hand, if you plan to meet in July of one year and then not meet again until two years later, then you will have biennial meetings.
The word “bicentennial” also has a very specific meaning.
- bicentennial: two hundredth anniversary of an event
We often see this word in relation to the celebrations of a country’s founding. For example, in 1976, the United States of America celebrated its bicentennial with lots of red, white and blue decorations and memorabilia.