bi·​an·​nu·​al | \ (ˌ)bī-ˈan-yə(-wə)l How to pronounce biannual (audio) \

Definition of biannual

1 : occurring twice a year

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Other Words from biannual

biannually adverb

What do bimonthly and biweekly mean?: Usage Guide

Many people are puzzled about bimonthly and biweekly, which are often ambiguous because they are formed from two different senses of bi-: "occurring every two" and "occurring two times." This ambiguity has been in existence for nearly a century and a half and cannot be eliminated by the dictionary. The chief difficulty is that many users of these words assume that others know exactly what they mean, and they do not bother to make their context clear. So if you need bimonthly or biweekly, you should leave some clues in your context to the sense of bi- you mean. And if you need the meaning "twice a," you can substitute semi- for bi-. Biannual and biennial are usually differentiated.

Did You Know?

When we describe something as biannual, we can mean either that it occurs twice a year or that it occurs once every two years. So how does someone know which particular meaning we have in mind? Well, unless we provide them with a contextual clue, they don't. Some people prefer to use semiannual to refer to something that occurs twice a year, reserving biannual for things that occur once every two years. This practice is hardly universal among English speakers, however, and biannual remains a potentially ambiguous word. Fortunately, English also provides us with biennial, a word that specifically refers to something that occurs every two years or that lasts or continues for two years.

Examples of biannual in a Sentence

Politicians still tremble when Barry begins his biannual comeback flirtations.  … But if they'd spent less time looking over their shoulders and more time looking over election returns, they'd have seen that Barry was likely heading for a poleaxing when he called it quits. — Michael Schaffer, New Republic, 22 Apr. 2002 … have recommended routine annual or biannual mammographic screening for asymptomatic women without a personal or family history of breast cancer, starting at the age of 40. — Nels Marcus Thygeson, Journal of the American Medical Association, 8 July 1986 One of the more fascinating commonplace facts about the whitetail is its biannual change of color. Summer, when deer come "into the red," as the saying goes, scant reddish-brown hairs replace the winter coat. Fall, deer come back "into the blue," though less than blue, with a thick pelage of hollow, grayish-tan hairs … — John G. Mitchell, Smithsonian, November 1982 The group holds biannual meetings in December and July. The art show is a biannual event that won't happen again for two more years.
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Recent Examples on the Web In September, he was invited to a biannual global meet-up at the Waze office in Tel Aviv, along with 70 of his peers from around the world to discuss what’s working and what isn’t. Alyssa Newcomb, Fortune, "What Makes People Love Waze More Than Google Maps and Apple Maps? Its Army of Unpaid Human Editors," 26 Nov. 2019 In celebration of its 25th anniversary, Urban Harvest set the stage for autumn's biannual Sunday Supper at St. John's School in River Oaks. Amber Elliott, Houston Chronicle, "VIP view: Urban Harvest taps 25 celebrity chefs for 25th anniversary Sunday Supper in River Oaks," 5 Nov. 2019 The biannual reports are a model of transparency and constructive criticism. The Denver Post Editorial Board, The Denver Post, "Editorial: Aurora’s police department needs to be “fixed.” Now’s the perfect time to do it.," 1 Nov. 2019 The Tolland County Chamber of Commerce is preparing for its biannual ‘Evening of Elegance’ event, which will take place at Maneeley’s in South Windsor, on Nov. 16. Steve Smith,, "Chamber’s ‘Evening Of Elegance’ Auction Set For Nov. 16," 29 Oct. 2019 The blast from the powder keg-like eruptions signaled that Mexican superstar Canelo Alvarez was back in town preparing for his biannual bout, looking bigger, literally, and hoping to prove better than ever. Manouk Akopyan, Los Angeles Times, "Canelo Alvarez looking to crush Sergey Kovalev, win title in fourth division," 23 Oct. 2019 The Biennale, the biannual contemporary art fair that closes next weekend, repened to the public on Thursday and received over 1,500 visitors., "Young Venetians volunteer after flood of their lifetimes - The Boston Globe," 17 Nov. 2019 The bank announced the move at its Texas Regional Partner Summit, a biannual meeting of figures and organizations working in affordable housing, small business development and economic inclusion. William Thornton |, al, "BBVA pledges $15.5 billion to community development," 31 Oct. 2019 Lions mailbag: How this roster compares to the rest of the NFC North Up until arriving in Detroit on Monday Fales had never crossed paths with Stafford, other than their biannual meetings when Fales was in Chicago. J.l. Kirven, Detroit Free Press, "How new Detroit Lions QB David Fales plans to win backup job," 13 June 2019

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

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First Known Use of biannual

1877, in the meaning defined at sense 1

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Time Traveler for biannual

Time Traveler

The first known use of biannual was in 1877

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Last Updated

9 Dec 2019

Cite this Entry

“Biannual.” The Dictionary, Merriam-Webster Inc., Accessed 11 December 2019.

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More Definitions for biannual


How to pronounce biannual (audio)

English Language Learners Definition of biannual

: happening twice a year
: happening every two years

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More from Merriam-Webster on biannual

Rhyming Dictionary: Words that rhyme with biannual

Spanish Central: Translation of biannual

Nglish: Translation of biannual for Spanish Speakers

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