anomaly

American  

[uh-nom-uh-lee] / əˈnɒm ə li /

noun

plural

anomalies

1. a deviation from the common rule, type, arrangement, or form.

   Synonyms:

   exception, aberration, abnormality

2. an anomalous person or thing; one that is abnormal or does not fit in.

   With his quiet nature, he was an anomaly in his exuberant family.

   Synonyms:

   exception, aberration, abnormality

3. an odd, peculiar, or strange condition, situation, quality, etc.

4. an incongruity or inconsistency.

5. Astronomy. a quantity measured in degrees, defining the position of an orbiting body with respect to the point at which it is nearest to or farthest from its primary.

6. Meteorology. the amount of deviation of a meteorological quantity from the accepted normal value of that quantity.

7. Grammar. irregularity.

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anomaly British  

/ əˈnɒməlɪ /

noun

1. something anomalous

2. deviation from the normal or usual order, type, etc; irregularity

3. astronomy

   1. Also called: true anomaly.  the angle between a planet, the sun, and the previous perihelion of the planet

   2. Also called: eccentric anomaly.  the angle between the periapsis of a particular point on a circle round the orbit as seen from the centre of the orbit. This point is obtained by producing a perpendicular to the major axis of the ellipse through the orbiting body until it reaches the circumference of the circle

   3. Also called: mean anomaly.  the angle between the periapsis of an orbit and the position of an imaginary body orbiting at a constant angular speed and in the same period as the real orbiting body

4. geology

   1. Also called: gravity anomaly.  a deviation from the normal value of gravity at the earth's surface, caused by density differences at depth, for example those caused by a buried mineral body

   2. Also called: magnetic anomaly.  a magnetic field, for example one produced by a buried mineral body, that deviates from an expected or standard value, usually that of the earth's magnetic field

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Other Word Forms

• anomalistic adjective
• anomalistically adverb

Etymology

Origin of anomaly

First recorded in 1565–75; from Latin anōmalia, from Greek anōmalía, equivalent to anṓmal(os) “irregular” + -ia noun suffix; anomalous, -ia

Explanation

An anomaly is an abnormality, a blip on the screen of life that doesn’t fit with the rest of the pattern. If you are a breeder of black dogs and one puppy comes out pink, that puppy is an anomaly. The noun anomaly comes from the Greek word anomolia, meaning "uneven” or “irregular.” When something is unusual compared to similar things around it, it’s the anomaly. If you are an Olympian who comes from a family of bookish types who all find it strenuous to walk the dog, you are an anomaly.

Example Sentences

But a digital forensics expert told AFP's fact-checkers that the anomaly was the result of a failed text overlay by a news station that had syndicated the official feed.

From Barron's • Apr. 11, 2026

His words were an anomaly in the history of presidential rhetoric.

From Salon • Apr. 8, 2026

“The likelihood that the M767A1 fuze malfunctioned is a statistical anomaly that was outside any reasonable probability.”

From Los Angeles Times • Mar. 16, 2026

Looking ahead, Forte hopes to explore whether the strengthening gravity anomaly played a role in shaping Antarctica's ice sheets.

From Science Daily • Mar. 7, 2026

So it was perhaps understandable that during Dr. Muller’s house calls we failed to mention the troubling anomaly of Lefty’s multiple strokes.

From "Middlesex: A Novel" by Jeffrey Eugenides

Related Words

• aberration
• abnormality
• deviation
• inconsistency
• irregularity
• oddity
• rarity