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

Joined by star Regina King and director Nicole Kassell, Lindelof took the stage Wednesday at the Television Critics Assn. biannual press tour in Beverly Hills to discuss the series. Los Angeles Times, "HBO’s ‘Watchmen’ TV show won’t mess with Alan Moore’s comic: ‘It’s canon’," 24 July 2019 Under Russo's recommendation, the city would provide appointments by neighborhood on a similar biannual schedule. Jen Fifield, azcentral, "Want bulk trash pickup? You'll have to pay in these 2 metro Phoenix cities," 8 July 2019 The Pistons will use the full biannual exception (worth $3.6 million) to address their frontcourt depth by adding the eight-year veteran. Vince Ellis, Detroit Free Press, "Here's what the Detroit Pistons hope Markieff Morris will bring to the team," 2 July 2019 This Saturday at Sqirl, Jessica Koslow’s East Hollywood toast palace hosts the first meeting of the Pastry Action Network (P.A.N.), a biannual bake sale showcasing the work of five pastry chefs from around the country. Amy Scattergood,, "The Pastry Action Network may be the new world order of bake sales," 27 June 2019 But in 2015 -- the same year DragCon, the biannual event RuPaul’s Drag Race launched, first took place in Los Angeles -- Morris made a drastic shift. Billboard Staff, Billboard, "Jobs of Tomorrow 2019: Take a Peek Into Music's Future," 27 June 2019 The research, done by University of Washington sociologists, analyzed filings in Washington state between 2001 and 2015 and found the biannual pattern. Ryan W. Miller, USA TODAY, "Divorces spike in the summer. Here's how to prepare for the end, experts say," 24 June 2019 When free agency begins 6 p.m. Sunday, the Pistons will have the $9.2 million non-taxpayer mid-level exception and $3.6 million biannual exemption to address roster needs. Vince Ellis, Detroit Free Press, "Looking for Detroit Pistons fits in free agency? Here are 10 names to watch," 14 June 2019 El Tri remains unbeaten in Gold Cup tests at Mile High, and just got one step closer to claiming its first title in CONCACAF’s biannual summer showcase since 2015. Sean Keeler, The Denver Post, "Mexico clinches Gold Cup quarterfinals slot with 3-1 win over Canada at Broncos Stadium," 19 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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Statistics for biannual

Last Updated

5 Aug 2019

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Time Traveler for biannual

The first known use of biannual was in 1877

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More Definitions for biannual



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

Comments on biannual

What made you want to look up biannual? Please tell us where you read or heard it (including the quote, if possible).


not constant or steady

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