A departure from the ordinary type: an irregularity or monstrosity.
noun
(rare)
Alternative form of [i]abnormality[/i] [First attested in the mid 18 th century.]Lesley Brown (editor), The Shorter Oxford English Dictionary, 5th edition (Oxford University Press, 2003 [1933], ISBN 978-0-19-860575-7), page 6
noun
A monstrosity [First attested in the mid 19 th century.]
departure from the ordinary type
An anomaly, malformation, or difference from the normal.