Pleonekteo (πλεονεκτέω) means to take advantage of, to overreach, to defraud, or to exploit. Literally 'to have more' (from pleon + echo), it describes gaining at another's expense — the predatory desire to acquire more than one's fair share by taking from others.
Paul warns about Satan's schemes in 2 Corinthians 2:11: 'in order that Satan might not outwit us.' The verb reveals that Satan operates through exploitation — taking advantage of unforgiveness to gain ground. In 1 Thessalonians 4:6, Paul warns against taking advantage of a brother in sexual purity. In 2 Corinthians 7:2 and 12:17-18, Paul defends against accusations of financial exploitation. The consistent usage reveals that pleonekteo is the opposite of love — while love gives, exploitation takes. It is the behavior of those who treat people as resources to be used rather than souls to be served.