deviation from the normal or common order or form or rule
"The sudden spike in server temperatures was an anomaly that disrupted our entire workflow."
a person who is unusual
"The coach was worried because his star player, an anomaly in our team's lineup, had been injured before the championship game."
(astronomy) position of a planet as defined by its angular distance from its perihelion (as observed from the sun)
"The astronomer calculated the anomaly to determine exactly where Mars would appear in the sky relative to its closest approach to the Sun."
A deviation from a rule or from what is regarded as normal; an outlier.
"The sudden spike in server temperatures was just an anomaly that disappeared after we rebooted the system."
The word comes from Latin anomalia, which was borrowed from Ancient Greek anōmalía meaning "irregularity." It is formed by negating the idea of something being even or smooth.