carrybacknoun
also carry-back, carry back uk/ˈkæriˌbæk/us[ U ] ACCOUNTING, TAX the practice of treating a company's present profit or loss as if it happened in an earlier period:
These charges can be deducted as if they were trading losses for the purpose of carry-back of losses.
[ C ] ACCOUNTING an amount that is copied from a later column of numbers or a later accounting period to an earlier one
[ U ] UK TAX a rule that allows an employee to count this year's payments into their pension fund as if they were made in the previous tax year:
Carry back gives an opportunity for immediate tax relief.