biannual

adjective

bi·an·nu·al (ˌ)bī-ˈan-yə(-wə)l

: occurring twice a year

: biennial sense 1

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.

Example Sentences

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 society is a members-only group who enjoy the perks of unique culinary experiences, including biannual dinners.

Alexa Gagosz, BostonGlobe.com, 2 Dec. 2022 The independent nonprofit released its biannual Fall 2022 hospital safety rankings on Nov. 16.

Caroline Catherman, Orlando Sentinel, 23 Nov. 2022 That’s why vets often recommend biannual wellness exams for senior dogs and cats.

San Antonio Express-News, 17 Nov. 2022 Among the evidence: Americans experience physical health problems caused by the biannual time changes, according to a study by the National Institutes of Health.

Frank Witsil, Detroit Free Press, 2 Nov. 2022 Shop markdowns on clothes, shoes, handbags, and accessories during the biannual Private Sale, running from Thursday, September 1 through Monday, September 5.

Alex Warner, Peoplemag, 31 Aug. 2022 The biannual New Haven Restaurant Week will return Oct. 16-29, with 23 restaurants in the city offering special deals.

Susan Dunne, Hartford Courant, 12 Oct. 2022 The program provides participating schools with sources of scholarships, access to Music Biz’s biannual #nextgen_u student summits and more.

Billboard Staff, Billboard, 11 Oct. 2022 In its biannual World Economic Outlook report published Tuesday, the IMF said global growth is expected to fall from 6% in 2021 to 3.2% this year and 2.7% in 2023—0.2 percentage points lower than its forecast just three months ago.

Jonathan Ponciano, Forbes, 11 Oct. 2022 See More

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.