For example, a "single account" is one account category that includes deposits in checking, savings accounts, money market deposit accounts and time deposits such as certificates of deposit (CDs).

FORBES: Magazine Article

Be aware that taking money out of a retirement account or selling securities at a sizable taxable gain rather than pulling cash from a certificate of deposit, money-market fund, savings or checking account could result in higher taxes on Social Security benefits if it bumps income above a certain threshold.

WSJ: How to Make Your Retirement Savings Last

But if you have less than five years before your kid sits down to freshman composition, a risk-free certificate of deposit, money market fund or even a traditional savings account is a better bet.

FORBES: Start Saving For College Now