1. taking effect from a date in the past rather than from the present or future
Usage: legal; formal

Examples

• The new tax law is retroactive to January 1st.
• She received a retroactive pay raise covering the past six months.
• The company’s policy changes are not retroactive.
• The court ruling had retroactive effects on previous cases.
• His promotion came with retroactive benefits.
• The insurance coverage was made retroactive to the accident date.