retroactive
🇺🇸
/ˌretrəʊˈæktɪv/
🇬🇧
/ˌretrəʊˈæktɪv/
adjective
R
Affecting something that happened in the past and applying it to the present.
The new law made the tax changes retroactive, so they applied to all past transactions.
新法律使稅收變更具有追溯效力，因此它們適用於所有過去的交易。
translation
追溯