- occurring every three years.
- lasting three years.
- a third anniversary.
- something that appears or occurs every three years.
- a period of three years; triennium.
Origin of triennial
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for triennial
For years, the triennial confab has been remarkable mostly for airy oratory by national leaders playing to the crowd back home.Summit of the Americas in Cartagena Will Be a Minefield for Obama
April 13, 2012
Lupton, Cara McCarty, Matilda McQuaid, and Cynthia Smith curated the Triennial.The Curator's Tale
July 7, 2010
The number of graduates, as appears from the triennial catalogue, is 3,191.
We turn again to the Triennial, and count the starred names.The Education of American Girls
Anna Callender Brackett
Read his report made to the stockholders at their triennial meeting in 1822.Thirty Years' View (Vol. I of 2)
Thomas Hart Benton
They did so, and found nothing hut a Harvard Triennial Catalogue.The Luck of Roaring Camp and Other Tales
The former was in favor of septennial, the latter of triennial parliaments.Junius Unmasked
- relating to, lasting for, or occurring every three years
- a third anniversary
- a triennial period, thing, or occurrence
C17: from Latin triennium
Word Origin and History for triennial
Online Etymology Dictionary, © 2010 Douglas Harper