To move funds or an investment from one position or investment to another. In the case of retirement funds specifically, an investor may roll over those funds from one account to another. This often occurs in the case of a 401(k) retirement plans when an employee leaves the company. Another common use is with certificates of deposits (CDs). CDs may be rolled over into another CD when they mature; the new CD will have a different interest rate. Another common use is with debt: Debtors or banks may allow their clients to roll over their debt into a new issue.