Semicentennial
Something that happens every six years is sexennial.
the word is novennial....
A triennial event happens every three years.
It is a triennial event. A triennial event happens three times a year.
Biennial or biannual can refer to something which happens every two years.
Something that happens every six years is sexennial.
the word is novennial....
The word "biennial" means an event that either lasts for two years, or it happens every two years.
A triennial event happens every three years.
It is a triennial event. A triennial event happens three times a year.
nothing
bidecadal
I think you are asking about a census.
Chicago Cubs in the World Series?
Leap year
True.
Every 100 years is called a century, made up of 10 decades.