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

Definition of biannual

1 : occurring twice a year

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 Pressig said the repairs are predicated on Pavement Condition Ratings (PCR), a biannual study that sets road repair priorities based on road wear and tear. Jesse Wright,, 11 Jan. 2022 Marines from Europe and the region operate throughout the continent for training and exercises, the Pentagon said, and thousands of Marines from II Marine Expeditionary Force will take part next year in the biannual Cold Response exercise in Norway. Oren Liebermann, CNN, 8 Dec. 2021 Pelicans, phalaropes, grebes, avocets and dozens of other species flock to the lake’s shores to nest or rest during their biannual journeys. Brian Maffly, The Salt Lake Tribune, 22 Nov. 2021 Despite the pandemic, the school continued to host its biannual shows — but with no one in the audience for the fall semester. Paulina Pearson, San Antonio Express-News, 30 Nov. 2021 The board also unanimously approved Koehler’s five-year forecast, a biannual requirement of the Ohio Department of Education, though the projections always involve multiple variables. cleveland, 17 Nov. 2021 Internal audits can be conducted by your own Information Security Department, while annual or biannual audits can be planned through a third party. Abdul Subhani, Forbes, 11 Oct. 2021 No matter where the Ravens and Bengals end up in the division this year, Sunday’s game looks like the first round of a biannual heavyweight bout. Jonas Shaffer,, 22 Oct. 2021 As part of the interior renovation, Chef Boulud has created a dedicated series of biannual exhibitions to be installed in the historic neoclassical dining room, the intimate Upper Lounge and the private Bellecour Room. Melissa Kravitz Hoeffner, Forbes, 28 Sep. 2021

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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The first known use of biannual was in 1877

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Last Updated

15 Jan 2022

Cite this Entry

“Biannual.” Dictionary, Merriam-Webster, Accessed 20 Jan. 2022.

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English Language Learners Definition of biannual

: happening twice a year : semiannual
: happening every two years : biennial

More from Merriam-Webster on biannual

Nglish: Translation of biannual for Spanish Speakers


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