A taking back or withdrawal; a denial of what one has previously said.
Example:
The following week, the newspaper reluctantly printed a retraction of the errors in the article, but the damage had been done.
The prefix re- ("back") gives retraction the meaning of "drawing back." Someone who has been wrongly accused may demand a retraction from his accuser -- though today it seems more likely that he'll just go ahead and sue. Thousands of citizens were forced to publicly retract their "wrong" ideas by the Soviet government in the 1930s and the Chinese government in the 1960s. Retractions tend to be rather formal and rarely private.