a special provision allowing part of a net loss or of an unused credit in a given year to be apportioned over one or two preceding years, chiefly in order to ease the tax burden
Compare "> carryforward (sense 2)
Word origin
[1940–45; n. use of v. phrase carry back]
Examples of 'carryback' in a sentence
carryback
If you combine it with carryback, you can go back seven years, to the 1998-9 tax year.