- twice a week, and
- once every two weeks.
For instance see: http://encarta.msn.com/dictionary_1861590876/biweekly.html
So would someone please explain to me how it is possible to use the word biweekly without it being unclear? The only possible way I could imagine using it is something like this:
"Hi guys. Don't forget our biweekly meeting tomorrow. That is, our meeting that is held every Tuesday and every Friday, that is twice-weekly, and not every second week on Friday."It's enough to drive a man to drink. Oh. Don't mind if I do.