anom·​a·​ly | \ ə-ˈnä-mə-lē How to pronounce anomaly (audio) \
plural anomalies

Definition of anomaly

1 : something different, abnormal, peculiar, or not easily classified : something anomalous They regarded the test results as an anomaly.
2 : deviation from the common rule : irregularity
3 : the angular distance of a planet from its perihelion as seen from the sun

Did you know?

You might be familiar with the Greek word homos, which means "same." It is from this word that we get words like homonym, homogeneous, and homophone, all of which have to do with sameness or similarity. What does this have to do with anomaly? Although it's not obvious, homos is a part of the etymology of anomaly, too. Anomaly is a descendant of the Greek word anōmalos, which means "uneven" or "irregular." Anōmalos comes from the prefix a- (meaning "not") and the word homalos (meaning "even")—and homalos comes from homos.

Examples of anomaly in a Sentence

In approximately 10% of patients, autism can be explained by genetic syndromes and known chromosomal anomalies (most of which have recognizable features in addition to autism) … — Lauren A. Weiss et al., New England Journal of Medicine, 14 Feb. 2008 Eleven minutes may not sound like much when you're waiting for a table at your favorite restaurant, but in the course of centuries, eleven minutes and change become a formidable chunk of time. By the 1300s, those superfluous minutes had added up to hours, then days, then more than a week. The calendar was losing time, irrevocably, to the "real" year, slipping further and further behind in its measurement of the earth's orbit. Anomalies began to creep into what had been the certainties of life. The spring equinox—one of two moments in the year when day and night are of equal length all over the earth, and which occurs on or about March 21—began to fall on March 16, then 15, then 14. — Michelle Stacey, Harper's, December 2006 Californians aren't the only ones vexed by rolling brownouts and other power-supply anomalies. Everyday power spikes, surges, sags, and line noise cause computers, stereo equipment, televisions, telephones, and other delicate electronic equipment to go psychotic or have complete nervous breakdowns. Fortune, 25 June 2001 This policy may well have made sense back when steroid use was an anomaly. Now that bulking up with chemical help seems to be more popular than ever, it's incumbent on baseball to take action. — Steve Kettman, New York Times, 20 Aug. 2000 We couldn't explain the anomalies in the test results. her C grade is an anomaly, as she's never made anything except A's and B's before See More
Recent Examples on the Web But an anomaly just under the soil may cement its legacy in the annals of Chicago-area history. Paul Eisenberg,, 19 Dec. 2021 Grocery shopping is not typically a daily activity, but Miele is not an anomaly among Erewhon’s extremely devoted and spendy customer base. Andrea Chang, Los Angeles Times, 9 Dec. 2021 Gaspery Roberts travels through time, hunting for answers to a mysterious anomaly. Monitor Reviewers, The Christian Science Monitor, 13 Apr. 2022 It’s long past time for a paradigm shift away from a gender-bias biological model that has measured and treated the female body as an anomaly of an ideal healthy male body. Robyn Mcgillis, Outside Online, 5 Aug. 2020 Pundits note Sinema is much more vulnerable to a primary challenge than Manchin, who is a political anomaly in West Virginia—a state former President Donald Trump carried in 2020 by nearly 39 percentage points. Nicholas Reimann, Forbes, 31 Jan. 2022 There’s also the statistical anomaly that is Jahvon Quinerly’s perimeter shooting. Michael Casagrande |, al, 11 Feb. 2022 The small patch underneath Lenné Estate near Yamhill turned out to be a happy anomaly for Lutz. Michael Alberty | For The Oregonian/oregonlive, oregonlive, 7 Feb. 2022 Besides an anomaly against the Patriots, who the Texans were beating 22-9 in the third quarter before giving up 16 straight points, there aren't a lot of losses the Texans can point at and say those should have been wins. Matt Young, Chron, 13 Dec. 2021 See More

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

First Known Use of anomaly

1603, in the meaning defined at sense 3

History and Etymology for anomaly

see anomalous

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Time Traveler for anomaly

Time Traveler

The first known use of anomaly was in 1603

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Last Updated

23 May 2022

Cite this Entry

“Anomaly.” Dictionary, Merriam-Webster, Accessed 28 May. 2022.

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More Definitions for anomaly


anom·​a·​ly | \ ə-ˈnä-mə-lē How to pronounce anomaly (audio) \
plural anomalies

Kids Definition of anomaly

: something different, abnormal, strange, or not easily described


anom·​a·​ly | \ ə-ˈnäm-ə-lē How to pronounce anomaly (audio) \
plural anomalies

Medical Definition of anomaly

: a deviation from normal especially of a bodily part the infants demonstrated congenital anomalies personality anomalies

More from Merriam-Webster on anomaly

Nglish: Translation of anomaly for Spanish Speakers

Britannica English: Translation of anomaly for Arabic Speakers Encyclopedia article about anomaly


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