octennial
/ɑkˈtɛniəl/
adjective
- Occurring every eight years.
- The octennial census provides data on long-term population trends.
- The octennial festival draws visitors from all over the region.
- The committee holds an octennial review of the organization's bylaws.
- Lasting for eight years.
- The octennial contract was renewed after negotiations.
- She served an octennial term as the head of the foundation.
- The king's octennial reign was marked by peace and prosperity.