noun anom·a·ly \ ə-ˈnä-mə-lē \
|Updated on: 10 Jul 2018

Definition of anomaly

plural anomalies
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

Examples of anomaly in a Sentence

  1. 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 Medicine14 Feb. 2008
  2. 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 StaceyHarper'sDecember 2006
  3. 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. Fortune25 June 2001
  4. 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 KettmanNew York Times20 Aug. 2000
  5. We couldn't explain the anomalies in the test results.

  6. her C grade is an anomaly, as she's never made anything except A's and B's before

Recent Examples of anomaly from the Web

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.

Origin and Etymology of anomaly

ANOMALY Defined for English Language Learners


Definition of anomaly for English Language Learners

  • : something that is unusual or unexpected : something anomalous

ANOMALY Defined for Kids


noun anom·a·ly \ ə-ˈnä-mə-lē \

Definition of anomaly for Students

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

Medical Dictionary


noun anom·a·ly \ ə-ˈnäm-ə-lē \

medical Definition of anomaly

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

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