The Grammarphobia Blog

Happy quinquennial

Q: My wife and I belong to a group of 15 couples that celebrate each couple’s wedding anniversary divisible by five—the fifth, tenth, fifteenth, and so on. Can you invent a word for this? My attempts include “cincoversary,” “quinqueversary,” and “cinqueversary.” Any clever ideas?

A: There’s already a word, “quinquennial,” which is both a noun (“we’re celebrating our quinquennial”) and an adjective (“our quinquennial celebration”).

This isn’t exactly a household word, so it’s understandable that you didn’t know it. Only three of the standard dictionaries we checked recognize both the noun and the adjective.

The American Heritage Dictionary of the English Language (5th ed.) and the online Collins English Dictionary say the noun “quinquennial” can mean either “a fifth anniversary” or a period of five years.

The Random House Kernerman Webster’s College Dictionary doesn’t use the words “fifth anniversary,” but it describes a “quinquennial” as “something that occurs every five years.”

All three say the adjective “quinquennial” means occurring once every five years or lasting for five years.

Some other dictionaries recognize the adjective but not the noun.

For instance, Merriam-Webster’s Collegiate Dictionary (11th ed.) and Webster’s New World College Dictionary (4th ed.) give the usual definitions for the adjective “quinquennial.”

Those two dictionaries don’t recognize the noun “quinquennial.” But they do have entries for “quinquennium,” a noun that came into English in the early 1600s and means simply a period of five years, not something occurring every five years.

The Oxford English Dictionary, a comprehensive dictionary that traces the historical development of the language, has examples for the adjective “quinquennial” dating back to the 15th century.

The earliest OED citations for the noun “quinquennial” are from the 19th century, but the dictionary has examples of a noun “quinquenal” dating back to the 15th century, when it meant “an ecclesiastical office held for five years.”

For a time in the 1500s and 1600s, an adjective spelled “quinquennal”  meant the same thing as “quinquennial”—that is, occurring once every five years or lasting for five years.

Eventually the “-ennial” spelling won out for both the noun and the adjective when used in the sense you’re asking about—a five-year anniversary.

The OED says the English word “quinquennial” is derived from Latin, either from quinquennalis (occurring every five years or lasting five years) or from quinquennis (of five years or five years old). The roots are quinque (five) and annus (year).

The OED’s many written examples of “quinquennial” extend well into modern English. However, most of the noun uses are described as “rare” today, including the one meaning a fifth anniversary. Here are two of the OED’s citations for that usage:

“The hospital only begs widely every five years, and this year is our quinquennial” (from the Westminster Gazette, 1903).

“She does not wait for quinquennials or decennials. She celebrates every anniversary with all the zest of a child” (from a Tennessee newspaper, the Kingsport Times, 1934).

For the most part, according to OED citations, “quinquennial” is used as an adjective to mean covering a period of five years, lasting for five years, or occurring every fifth year. Here are modern citations for each meaning:

“He was a realist. Quinquennial Plans, Personal Development Schemes, Bribes, marriage deals—the barbarians are vanquished” (from Andrew Waterman’s poetry collection The End of the Pier Show, 1995).

“Each of the 163 minority groups documented … was scored for the most widespread and intense event reported during each quinquennial period” (from the Journal of Peace Research, 2000).

“A quinquennial valuation of the ‘Royal’ life and annuity business was made at December 31” (from the Times, London, 1955).

Despite the “rare” label in the OED, “quinquennial” is listed without comment in American Heritage, Collins, and Random House as a noun for a five-year anniversary or occurrence. So you can certainly use it.

But this is your celebration—you invented it, and you can call it what you want (we rather like the sound of “cinqueversary”). Whatever you decide, here’s a toast to all 30 of you!

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