Irrevocable

/ɪˈrɛvəkəbəl/ adjective medium

Impossible to change or take back once it has already been done.

Signing the contract was an irrevocable decision that neither side could undo, no matter how much they later regretted it.

Memory Trick

'Ir-' (not) plus 'revocable' (able to be called back) — an irrevocable choice can never be revoked.