Anomaly is a noun.

In astronomy or astrophysics mass concentration or mascon is a region of a planet or moon's crust that contains a large positive gravitational anomaly. In general, the word "mascon" can be used as a noun to describe an excess distribution of mass on or beneath the surface of a planet (with respect to some suitable average), such as Hawaii.[1] However, this term is most often used to describe a geologic structure that has a positive gravitational anomaly associated with a feature (e.g. depressed basin) that might otherwise have been expected to have a negative anomaly, such as the "mascon basins" on the Moon. -wiki

irregularity is the synonyms of anomaly

Anomaly means, essentially, irregularity. An example sentence would be: The anomaly of the necklace, is what she liked about it.

Anomaly - comics - was created in 1996.