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triennial

adjective tri·en·ni·al \(ˌ)trī-ˈe-nē-əl\

Definition of TRIENNIAL

1
:  occurring or being done every three years <the triennial convention>
2
:  consisting of or lasting for three years <a triennial contract>
— triennial noun
— tri·en·ni·al·ly \-nē-ə-lē\ adverb
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First Known Use of TRIENNIAL

1562

Rhymes with TRIENNIAL

biennial, centennial, decennial, millennial, perennial, quadrennial, quinquennial, septennial, vicennial

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