What does centennial mean?
A centennial is the hundredth anniversary of a notable event, most commonly the founding of an institution, city, organization, or nation. The word also functions as an adjective, describing anything that relates to a hundred years or to such an occasion — for example, a centennial celebration, a centennial edition of a book, or a centennial exhibition. Centennials are typically marked with ceremonies, publications, parades, and other commemorative activities that honor longevity and historical continuity. In American usage, 'centennial' is the standard term, while British English generally favors 'centenary'; both derive from the same Latin roots. Related terms built on the same pattern include sesquicentennial (150th anniversary) and bicentennial (200th anniversary), making 'centennial' part of a small family of words used to mark major milestones in time. Because anniversaries of this scale are rare and significant, the word carries a dignified, celebratory connotation and appears chiefly in formal writing, journalism, and official commemorations.
The hundredth anniversary of a significant event.
"The town's centennial drew thousands of visitors and former residents."
American English strongly prefers 'centennial'; British English typically uses 'centenary' for the same meaning.
Relating to a hundredth anniversary, or lasting or occurring over a period of one hundred years.
"The society issued a centennial history of the railroad."
When used attributively before a noun (e.g., 'centennial gala'), it almost always refers to a hundredth-anniversary observance.
The plural refers to multiple hundredth-anniversary events or celebrations.
"Both universities held their centennials within the same decade."
In American English we say 'centennial,' but in British English the same milestone is called a 'centenary' — same Latin root, different favorite suffix.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of centennial
The word 'centennial' comes from the Latin 'centum,' meaning 'one hundred,' combined with the adjectival suffix '-ennial,' from 'annus,' meaning 'year.' It entered English in the early 19th century, alongside its close cousin 'centenary,' which shares the same root. Other English words from the same Latin root 'centum' include 'century,' 'percent,' and 'centurion.'
How centennial is actually used
'Centennial' is the standard term in American English; British English typically prefers 'centenary.' The word carries a formal, celebratory register, appearing most often in institutional, civic, and commemorative contexts rather than casual conversation.
Easily confused with centennial
A bicentennial marks a two-hundredth anniversary, whereas a centennial marks a one-hundredth.