Retesting
Retesting re-runs the specific test cases that previously failed, after a fix has been applied, to confirm the exact reported defect is actually resolved. It's narrower and more targeted than regression testing, which checks that the fix didn't break anything else nearby.
Retesting and regression testing are frequently confused, but they answer different questions: retesting asks "did this specific fix work," regression testing asks "did fixing it break something else." A responsible defect-fix cycle does both — retest the exact failing case, then run a relevant slice of the regression suite around it.
Skipping retesting in favor of just trusting the fix is a common corner-cutting mistake — code review can miss whether a fix actually addresses the reported symptom under the same conditions the original bug report described.
