irrevocable

形容词 irrevocable:

1. incapable of being retracted or revoked- Shakespeare
   同义词：irrevokable

1. In irrevocable letter of credit in your favour, payable in ... against shipping documents.
   如果我方接受你方发盘，将开立以你方为受益人的不可赊销信用证在。。。付款交单。
2. The decision has been made and is irrevocable.
   木已成舟已作出决定，无法反悔
3. Jove gives his promise, and confirms it with the irrevocable oath, attesting the river Styx, terrible to the gods themselves.
   朱庇特应允了，还发誓绝不食言，且指定冥河斯提克斯——众神听了都要发抖的名字——做他的监誓人。
4. I am sorry to say the only term of payment we can accept is100% irrevocable documentary letter of credit.
   抱歉地说，我们能接受的付款条件只有100％不可撤销跟单信用证。

ir.rev.o.ca.ble

adj.（形容词）
Impossible to retract or revoke:
不能撤回的或不可废止的：
例句：
an irrevocable decision.
不能撤回的决定

【引伸】
irrev.ocabil.ity 或
irrev.ocableness
n.（名词）
irrev.ocably
adv.（副词）