triennium

noun

tri·​en·​ni·​um trī-ˈe-nē-əm How to pronounce triennium (audio)
plural trienniums or triennia trī-ˈe-nē-ə How to pronounce triennium (audio)
: a period of three years

Word History

Etymology

Latin, from tri- + annus year — more at annual

First Known Use

1847, in the meaning defined above

Time Traveler
The first known use of triennium was in 1847

Dictionary Entries Near triennium

triennial

triennium

triens

See More Nearby Entries 

Cite this Entry

“Triennium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/triennium. Accessed 21 Dec. 2024.

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