Cunning schemes, crafty strategies, or manipulative methods. Paul uses it twice in Ephesians, warning against deceptive teaching tactics (4:14) and urging believers to armor up against the devil's schemes (6:11). The word emphasizes methodology—calculated, systematic deception rather than impulsive lying. Later Greek used it for methods of collecting taxes or debts, but Paul's usage is clearly negative: sophisticated error wrapped in persuasive strategy.