To make amends for one's past misdeeds or shortcomings by doing something positive. Matt's grades were not great at the beginning of the semester, but he's totally redeemed himself and gotten A's on every test since. My sister was mad at me for not spending time with her, so I redeemed myself by getting us tickets to see her favorite band.
See also: redeem
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.