biannual

adjective

bi·​an·​nu·​al (ˌ)bī-ˈan-yə(-wə)l How to pronounce biannual (audio)
1
: occurring twice a year
2
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.
Recent Examples on the Web The biannual temporal event allows for more daylight at night between mid-March to early November. Skyler Caruso, Peoplemag, 9 Mar. 2024 Most of the rest of us are set to repeat the biannual dance. TIME, 9 Mar. 2024 There is one possible option to reduce the biannual crush on the ballot: reduce the number of judge retention questions. Mary Jo Pitzl, The Arizona Republic, 3 Mar. 2024 The custom versions, which require getting measured at one of the company’s biannual trunk shows in New York or at a participating retailer, are available in two grades of manufacturing: Black Line and Gold Line. Aleks Cvetkovic, Robb Report, 2 Mar. 2024 The Sacramento Bee consulted Johns Hopkins Bloomberg School of Public Health and National Geographic to understand the origin of daylight saving time and how the biannual time change came to be. Brianna Taylor, Sacramento Bee, 28 Feb. 2024 Development for small drones and a raft of other systems must be done at a monthly pace rather than the quarterly, yearly or biannual pace of the past. Eric Tegler, Forbes, 21 Feb. 2024 Hemispheric supply-chain ecosystems cannot be developed through a handful of biannual meetings of heads of state. Shannon K. O’Neil, Foreign Affairs, 20 Feb. 2024 In 2008, 71 percent of Americans acknowledged that climate change was happening, according to a long-running biannual survey conducted by the Yale Program on Climate Change Communication and George Mason University. Delger Erdenesanaa, New York Times, 6 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'biannual.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1877, in the meaning defined at sense 1

Time Traveler
The first known use of biannual was in 1877

Podcast

Dictionary Entries Near biannual

Cite this Entry

“Biannual.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/biannual. Accessed 19 Mar. 2024.

Kids Definition

biannual

adjective
bi·​an·​nu·​al (ˈ)bī-ˈan-yə(-wə)l How to pronounce biannual (audio)
: occurring twice a year
biannually
adverb

More from Merriam-Webster on biannual

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!