The name has been "Flight Review" for almost 20 years now. "Biennial" went away when the FAA considered flight reviews every 12 months for less experienced pilots and every 24 for those with more experience. Thankfully this onerous provision died before becoming policy.
Using the proper term avoids the possible mistake of "biannual" (twice per year) vs. "biennial" (every second year).
I shouldn't be too pedantic on a forum where I don't normally post; I want to spend a Christmas holiday in NZ one year soon and ditto for Australia one year. I'll need advice when the time comes!