/rɛtrəˈspɛktɪv lɔː/ – Phrase
Definition: (Anh) đạo luật có hiệu lực hồi tố, đạo luật có hiệu lực trở về trước.
A more thorough explanation: A retrospective law is a law that applies to events that occurred before the law was enacted. It is also known as a retroactive law.
Example: The new tax legislation included a retrospective law that applied the increased tax rate to income earned in the previous year.