The phrase "abnormal activity" refers to something that is not usual or usual behavior. It means an action or behavior that is different from what is normally expected or considered normal. Full definition
But for those with REM sleep behavior disorder, abnormal activity in the brain stem prompts the system to break down. (discovermagazine.com)
To observe any suspicious or abnormal activities on the post. (livecareer.com)
Typical resume samples for this job highlight duties like strengthening information systems, running tests, developing network line defense, preventing unauthorized access, and detecting abnormal activity. (jobhero.com)