Annual event
biannual
biannual...
Biannual
A eight day festival called "Paryushan Parv" is regarded as major event for the Jains. It occurs in the months of August-September every year.
a persons birthday on the day of a leap year
People born on a double leap year
Australian Open - Tennis
Biannual
An annual event occurs once a year.
Biannual can be used in a sentence as an adjective to denote an event that occurs twice a year, or every two years. So, "It's a biannual event" is a rather ambiguous statement.
Yes, every year there is an event called Pogopalooza, hosted by Xpogo.com
An event occurs 2 times in a year