To cause someone or oneself to be mentally and emotionally prepared, obdurate, and unyielding in the face of some difficult or unpleasant person, task, situation, outcome, etc. The future may look grim, but we must steel ourselves against the challenges ahead. Our people have long been steeled against would be tyrants like you! I know I'm tough on you, but I'm trying to steel you against life's many difficulties and disappointments.