retroactive

adj

1. affecting things past

e.g. retroactive tax increase
an ex-post-facto law
retro pay

Synonym: ex post factoretro

2. descriptive of any event or stimulus or process that has an effect on the effects of events or stimuli or process that occurred previously

1. （决定或行为）有追溯效力的
If a decision or action is retroactive, it is intended to take effect from a date in the past.

e.g. There are few precedents for this sort of retroactive legislation.
这种有追溯力的法规鲜有先例。

1. 有追溯效力的：retrieval 检索 | retroactive 有追溯效力的 | retrofit 改型

2. 反作用的;追溯的：retroactive effect 反馈作用 | retroactive 反作用的;追溯的 | retroarc basin 弧后盆地

3. 反动的：retroaction 反动 | retroactive 反动的 | retroactively 逆动地

4. 倒摄的：retroaction 逆作用 | retroactive 倒摄的 | retroactive amnesia 倒摄遗忘