noun, noun which may take the genitive case particle 'no'
Refers to a bad person, often with a nuance of criminality or moral corruption. Can be used seriously or lightly.
He is a notorious villain in town.
A gang of scoundrels robbed the bank.
A villain appeared in the town and caused trouble for the people.
The police finally caught the villain.
He joined a gang of villains to make money.
悪者 is the common, everyday word for a villain (often in stories), whereas 悪党 sounds harder-edged and more like a real criminal.
悪漢 is a somewhat literary word for a scoundrel or ruffian, similar in toughness to 悪党 but less used in casual speech.
悪党 carries a stronger sense of organized wrongdoing or villainy, whereas 悪 is a lighter, more colloquial label for a bad guy.
善人 means a good, virtuous person, the direct opposite of 悪党's bad, criminal character.
Compound of 悪 (aku, 'bad, evil') and 党 (tō, 'party, faction, group'). Originally referred to a group of evildoers or a faction of villains, later extended to individuals.