Do you mean irreversible change? If so it means "It can not be changed".
no
reversable
irreversible
irreversible change.
IRREVERSIBLE
irreversible change
Burning something is irreversible.
The antonym of irreversible would be reversible.
Rusting is an irreversible process.
irreversible
Irreversible
of course its irreversible because once you have cooked the popcorn you cannot turn it back into what it was and originally they were small grains of corn