abnormal
Definitions
Deviating from what is normal, usual, or typical, often in a way that is undesirable or concerning.
Not conforming to a standard, rule, or expected pattern.
Examples
The doctor noticed an abnormal growth during the routine examination.
It is quite abnormal for the temperature to drop so drastically in the middle of July.
The software began to show abnormal behavior after the latest update was installed.
Synonyms
unusual irregular atypical anomalous deviant peculiar strange