Meaning of quadrennial

quad•ren•ni•al

Pronunciation: (kwo-dren'ē-ul), [key]
— adj.
  1. occurring every four years: a quadrennial festival.
  2. of or lasting for four years: a quadrennial period.
—n.
  1. an event occurring every four years, as an anniversary or its celebration.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.