Triennial(a.)
- Continuing three years; as, triennial parliaments; a triennial reign.
Triennial(a.)
- Happening, coming about, or appearing once in every three years; as, triennial elections; a triennial catalogue; a triennial visitation.
Triennial(n.)
- Something which takes place or appears once in three years.
Trienniality
- Sorry, we do not have a definition for this word