irrepealable

adj

1. That cannot be repealed.

   “Is the impious edict irrepealable?”

   “It was anticipated in the writer's work on constitutional law ("Federal and State Constitutions," p. 186, note 8): "The enabling acts admitting the eight new Western States usually provided against polygamy on account of the Mormon influence, and this, with other provisions concerning schools, etc., was made forever irrepealable without the consent of the United States; see Utah 3, 1.”