de·​cen·​ni·​um di-ˈse-nē-əm How to pronounce decennium (audio)
plural decenniums or decennia di-ˈse-nē-ə How to pronounce decennium (audio)
: a period of 10 years : decade

Example Sentences

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, 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.

Word History


Latin, from decem + annus year — more at annual

First Known Use

1685, in the meaning defined above

Time Traveler
The first known use of decennium was in 1685

Dictionary Entries Near decennium

Cite this Entry

“Decennium.” Dictionary, Merriam-Webster, Accessed 22 Mar. 2023.

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