Origin: Latin suffix -ive
Retroactive has 3 different meanings across 1 category:
descriptive of any event or stimulus or process that has an effect on the effects of events or stimuli or process that occurred previously
"The new tax policy had a retroactive impact, forcing us to recalculate our returns for last year even though we thought everything was settled."
affecting things past
"retroactive tax increase"
"an ex-post-facto law"
"retro pay"
Extending in scope, effect, application or influence to a prior time or to prior conditions
"The new tax law has retroactive effects that will require me to file amended returns for last year."