adjective ret·ro·ac·tive \-ˈak-tiv\

: effective from a particular date in the past

Full Definition of RETROACTIVE

:  extending in scope or effect to a prior time or to conditions that existed or originated in the past; especially :  made effective as of a date prior to enactment, promulgation, or imposition <retroactive tax>
ret·ro·ac·tive·ly adverb
ret·ro·ac·tiv·i·ty \-ˌak-ˈti-və-tē\ noun


  1. They all received a retroactive pay raise.
  2. The new tax will be retroactive to January 1.


French rétroactif, from Latin retroactus, past participle of retroagere to drive back, reverse, from retro- + agere to drive — more at agent
First Known Use: 1611

Other Legal Terms

actionable, alienable, carceral, chattel, complicity, decedent, larceny, malfeasance, modus operandi
Medical Dictionary


adjective ret·ro·ac·tive \ˌre-trō-ˈak-tiv\

Medical Definition of RETROACTIVE

:  having relation or reference to or efficacy in a prior time; specifically :  relating to, caused by, or being obliteration of the results of learning by immediately subsequent activity <retroactive inhibition>


Next Word in the Dictionary: retroactive inhibitionPrevious Word in the Dictionary: retroactionAll Words Near: retroactive
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comprehension or the fear of future evil
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