Nefarious implies a deep level of wickedness, often related to serious moral offenses, not minor wrongs. The criminal's nefarious plot was to embezzle funds from the charity.
Pro Tip 2/3
High Severity
'Nefarious' suggests actions that are extremely harmful or destructive, not just bad behavior. He was known for his nefarious deeds which caused devastation in the community.
Pro Tip 3/3
Covert Operations
Nefarious activities are often secretive, done under the radar to avoid detection. The agency uncovered the spy's nefarious activities that threatened national security.