Originally Posted by Bartelby
Biannual does mean twice a year.
Biennial means every second year.
I think some dictionaries may have decided that the word biannual is used for both and as they're descriptive and not prescriptive in nature they have changed the definition.
Where I come from the distinction is still pretty clear and I had no confusion as to what you meant.
Its good to know that Martians use the same word for Biannual.