quadrennialEnglishOxford New American Dictionaryquadrennial /kwäˈdrenēəl, kwɑˈdrɛniəl / ▸ adjective recurring every four years: the quadrennial world championships. ▪ lasting for or relating to a period of four years. – DERIVATIVES quadrennially /kwäˈdrenēəlē, kwɑˈdrɛniəli / adverb– ORIGIN mid 17th century : from quadrennium + -al.