The state or characteristic of being retroactive. (noun)
The application of a law to events that took place before it was made. (noun)
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Use "retroactivity" in a sentence
"In the small print, it seems there is a question of "retroactivity", which means that the ECJ has the option to waive backdated liabilities, in which case the net loss to the Treasury could be very small."
"Under the draft package, military service members should not apply for retirement so long as the Commission on the Disciplinary Sanctions of Public Functionaries is still screening relevant disciplinary cases involving them or the Control Yuan is screening relevant impeachment cases and that they will also be subject to the same "retroactivity" regulations."
"The amendment was controversial because it did not make any mention of retroactivity, meaning that President Compaore's eligibility to present himself for the 2005 presidential election was a matter of debate."