1. An action, behavior, or event that deviates from the normal or expected pattern; something that occurs infrequently or is out of the ordinary
The bank detected unusual activity on the account and froze it temporarily.
O banco detectou atividade incomum na conta e a congelou temporariamente.
2. In security contexts, any behavior that suggests a potential threat, breach, or anomaly requiring investigation
The system flagged unusual activity in the server logs.
O sistema sinalizou atividade incomum nos registros do servidor.