This verb means to clean by removing what is unproductive or contaminating. Its primary agricultural use involves pruning vines—cutting away dead or excess branches so the plant bears better fruit. In John 15:2, Jesus uses viticultural imagery: 'Every branch that bears fruit he prunes (kathairei) that it may bear more fruit.' The metaphor describes God's disciplinary care: he removes what hinders fruitfulness not to destroy but to maximize abundant life. Pruning involves painful loss in service of greater gain.