Every 100 years is called a century, made up of 10 decades.
An event occurring every two years is referred to as a biennial event. This pattern indicates that the event happens once every two years.
It is a triennial event. A triennial event happens three times a year.
Change.
A triennial event happens every three years.
Annual event
Something that happens every six years is sexennial.
yes i'm positive it happens every year
If something happens twice a month it is called biweekly because it happens every other week and a month has 4 weeks. there is also bimonthly which is every other month but not really a direct word for something that happens twice a month.
bidecadal
nothing
time passes