retraction

When you change your mind and take back something you said previously, that's a retraction. If a politician says something offensive, he'll sometimes issue a formal retraction later.

When someone needs to withdraw an opinion or backpedal on something they've said (especially publicly), they send out a retraction. A newspaper editor might publish a retraction after a badly reported story is printed, and astronomers who discover a new star might announce a retraction after realizing it was just a smudge on the lens of their telescope. The Latin root is retractionem, "a drawing back."