de·​cen·​ni·​um | \ di-ˈse-nē-əm How to pronounce decennium (audio) \
plural decenniums or decennia\ di-​ˈse-​nē-​ə How to pronounce decennia (audio) \

Definition of decennium

: a period of 10 years : decade

Examples of decennium in a Sentence

Recent Examples on the Web According to design firm Bagaar's blog: Over the past decennium, users have grown accustomed to certain design patterns: positions, colors, icons... Samuel Axon, Ars Technica, "Behold, the most (intentionally) poorly designed website ever created," 4 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'decennium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of decennium

1685, in the meaning defined above

History and Etymology for decennium

Latin, from decem + annus year — more at annual

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Time Traveler for decennium

Time Traveler

The first known use of decennium was in 1685

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Cite this Entry

“Decennium.” Dictionary, Merriam-Webster, Accessed 25 Oct. 2020.

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