In Roman family law, the power that the male head of a family (paterfamilias) exercised over his descendants in the male line and over adopted children. Originally this power was absolute and included the power of life and death; a paterfamilias could acknowledge, banish, kill, or disown a child. He could free his male descendants from this obligation or turn over his daughter and all her inheritance to the power of her husband. By the end of the republic (from about the 1st century BC), a father could inflict only light punishment and his sons could keep what they earned.
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