Definition of "anomaly"

anomaly

/əˈnɒm.ə.lɪ/

noun
plural anomalies
1. A deviation from a rule or from what is regarded as normal; an outlier.
  Quotations
  This ardent exploration, absorbing all his energy and interest, made him forget for the moment the mystery of his heritage and the anomaly that cut him off from all his fellows.
  1956, Arthur C. Clarke, The City and the Stars, page 43
2. Something or someone that is strange or unusual.
3. (sciences) Any event or measurement that is out of the ordinary regardless of whether it is exceptional or not.
4. (astronomy) Any of various angular distances.
5. (biology) A defect or malformation.
6. (quantum mechanics) A failure of a classical symmetry due to quantum corrections.
7. (dated) An irregularity or disproportion.