Source : Webster's Revised Unabridged Dictionary (1913)

Irrepealable \Ir`re*peal"a*ble\, a.
   Not repealable; not capable of being repealed or revoked, as
   a law. -- {Ir`re*peal"a*ble*ness}, n. -- {Ir`re*peal"a*bly},
   adv.