"Erratic behavior" refers to actions or conduct that is unpredictable, inconsistent, or irregular. It means behaving in a way that is erratic or out of the ordinary, and not maintaining a stable or predictable pattern of behavior. Full definition
The researchers investigated the impact of these vying forces to understand how climate warming is affecting the seemingly erratic behavior of the jet stream. (pnnl.gov)
She began experiencing seizures and displaying erratic behavior this week. (apocketfulofpolkadots.com)
Imagine you are serving on a jury: the defendant is charged with murder, but he also suffers from a brain tumor that causes erratic behavior. (scientificamerican.com)