retroactive
adj. C1 Advanced US //ˌɹɛtɹoʊˈæktɪv// UK //ɹˌɛtɹəʊˈæktɪv// retroac·tive
adj. relating to something that applies to a time in the past. You use this when a new rule or law starts working from a date that is already over.
adj. relating to or affecting a past period of time. Often describes legal or administrative changes that are applied to events or periods that have already occurred.
The new tax law is retroactive and applies to last year.
The company decided to offer a retroactive bonus to all employees who had worked there for more than five years.
The court ruled that the new safety regulations were retroactive, meaning that all previous violations of the old standards were now subject to the higher penalties of the current law.
First attested in 1610. From French rétroactif, equivalent to retro- + active.