1. To become more sympathetic or amenable and to do something previously ruled out or to allow something previously forbidden to take place.
2. To slacken or to become less intense; to soften in temper; to become more gentle or compassionate.
3. Etymology: "to melt, to soften, to dissolve", from re-, "again" + Latin lentus, "slow, viscous, supple". The sense of "become less harsh or cruel" was first recorded in 1526.