Word Study
retroact
CIDE DICTIONARY
retroact, v. i. [Pref. retro- + act.].
To act backward, or in return; to act in opposition; to be retrospective. [1913 Webster]
OXFORD DICTIONARY
retroact, v.intr.
1 operate in a backward direction.
2 have a retrospective effect.
3 react.
1 operate in a backward direction.
2 have a retrospective effect.
3 react.
Derivative
retroaction n.
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