And a rollover from a 401(k) is indeed a distribution from the 401(k). It's just that the portion of that distribution that is rolled over to a traditional IRA is a nontaxable distribution. If the rollover was a direct rollover to a traditional IRA, the Form 1099-R will have code G in box 7 and will have a zero in box 2a to indicate that the entire amount was rolled over and is nontaxable.
(If the code-G Form 1099-R has a blank box 2a, the payer mistakenly omitted the zero from box 2a and you should enter a zero in box 2a of TurboTax's 1099-R form. If box 2a of a code-G Form 1099-R has a nonzero amount in box 2a the form indicates a taxable rollover to a Roth account.)
