To have absolute authority in one's words; to speak with ultimate power, as if one's pronouncements are law and can decide fate.
他掌握着团队的最终决策权，凡是他口衔天宪的命令，无人敢不遵从。
He held ultimate decision-making power in the team; no one dared to disobey his commands, which were as if his words were law.
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