anomalous

adj. abnormal, irregular, unusual, exceptional

Anomaly may refer to:AstronomyEccentric anomaly, the angle between the direction of periapsis and the current position of an object on its orbitFlyby anomaly, an unexpected energy increase during Earth flybys of satellitesMean anomaly, a measure of time in the study of orbital dynamicsPioneer anomaly, the observed deviation of the trajectories of various unmanned spacecraftSouth Atlantic Anomaly, the region where Earth's inner van Allen radiation belt makes its closest approach to the planet's surfaceTrue anomaly, the angle between the direction of periapsis and the current position of an object on its orbit
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Adjective
1. deviating from the general or common order or type; "advanced forms of life may be anomalous in the universe"
(similar) abnormal

(a.)
Deviating from a general rule, method, or analogy; abnormal; irregular; as, an anomalous proceeding.
  

adjective
different from what is usual
anomalous pulmonary venous drainage = condition where oxygenated blood from the lungs drains into the right atrium instead of the left