If a decision, action, or change is irrevocable, it cannot be changed or reversed.
例句
It may well be worth waiting for better times before making any irrevocable commitment...最好等到更合適的時候再作出不能反悔的承諾。He said the decision was irrevocable.他說這項決定是不可改變的。
英漢詞典釋義
adj.
不可改變的, 不可反轉的
His life was set on an irrevocable course.他的生活道路不可改變。