anomaly.

An observation or case that departs from an expected pattern or rule.

Use it for

Words that belong together

• statistical anomaly
• explain an anomaly
• anomalous result

On the page

The sudden decline in recorded rainfall was an anomaly worth investigating.

What looked like an anomaly became predictable after the units were corrected.

The theory accommodates the main pattern but leaves two anomalies unexplained.

Usage notes

Primary category: academic. An anomaly may reveal an error, a limitation of the model, or a genuine unusual case. It is not automatically irrelevant or evidence of fraud. Singular: anomaly; plural: anomalies. Derived family (not inflections): anomalous.